between - A value or set of values which are greater than a lower value in a range and less than a higher value in a range
-65 times the difference between a number and 79 is equal to the number plus 98-65 times the difference between a number and 79 is equal to the number plus 98
The phrase [I]a number[/I] means an arbitrary variable. Let's call it x.
The first expression, [I]the difference between a number and 79[/I] means we subtract 79 from our arbitrary variable of x:
x - 79
Next, -65 times the difference between a number and 79 means we multiply our result above by -65:
-65(x - 79)
The phrase [I]the number[/I] refers to the arbitrary variable x earlier. The number plus 98 means we add 98 to x:
x + 98
Now, let's bring it all together. The phrase [I]is equal to[/I] means an equation. So we set -65(x - 79) equal to x + [B]98:
-65(x - 79) = x + 98[/B] <-- This is our algebraic expression
If the problem asks you to take it a step further and solve for x, then you [URL='https://www.mathcelebrity.com/1unk.php?num=-65%28x-79%29%3Dx%2B98&pl=Solve']type this equation into our search engine[/URL], and you get:
x = [B]76.31818[/B]
3 friends went to dinner and their total bill was $19.50. They each brought $8. If a tip is typicall3 friends went to dinner and their total bill was $19.50. They each brought $8. If a tip is typically between 15% and 20% of the bill do they have enough for dinner and tip?
15% tip:
19.50 * 1.15 = 22.43
20% tip:
19.50 * 1.2 = 23.4
3 friends each brought $8, so they have:
3 * 8 = $24
So the $24 [B]will cover both a 15% tip and a 20% tip[/B]
3 times a number increased by 1 is between -8 and 133 times a number increased by 1 is between -8 and 13.
Let's take this algebraic expression in [U]4 parts[/U]:
Part 1 - The phrase [I]a number[/I] means an arbitrary variable, let's call it x:
x
Part 2 - 3 times this number means we multiply x by 3:
3x
Part 3 - Increased by 1 means we add 1 to 3x:
3x + 1
The phrase [I]between[/I] means we have an inequality:
[B]-8 <= 3x + 1 <=13[/B]
3 times the difference between t and y3 times the difference between t and y
Difference between t and y
t - y
3 times this difference:
[B]3(t - y)[/B]
3-dimensional pointsFree 3-dimensional points Calculator - Calculates distance between two 3-dimensional points
(x1, y1, z1) and (x2, y2, z2) as well as the parametric equations and symmetric equations
31,29,24,22,17 what comes next31,29,24,22,17 what comes next
We see that each sequence term alternates between subtracting 2 and subtracting 5. Since the last term, 17, was found by subtracting 5, our next term is found by subtracting 2 from 17:
17 - 2 = [B]15[/B]
64 is 4 times the difference between Sarah's age, a, and 44. Assume Sarah is older than 44.64 is 4 times the difference between Sarah's age, a, and 44. Assume Sarah is older than 44.
The phrase [I]difference between[/I] means we subtract 44 from a:
a - 44
The phrase [I]64 is[/I] means an equation, so we set a - 44 equal to 64
[B]a - 44 = 64 <-- This is our algebraic expression
[/B]
If you want to solve for a, then we [URL='https://www.mathcelebrity.com/1unk.php?num=a-44%3D64&pl=Solve']type this expression into our search engine[/URL] and get:
[B]a = 108[/B]
64 is 4 times the difference between Sarah’s age a, and 44.Assume Sarah is older than 4464 is 4 times the difference between Sarah’s age a, and 44.Assume Sarah is older than 44
Difference between Sarah's age (a) and 44 (Assuming Sarah is older than 44):
a - 44
4 times the difference:
4(a - 44)
The word [I]is[/I] means equal to, so we set 4(a - 44) equal to 64 to get our algebraic expression:
[B]4(a - 44) = 64[/B]
If the problem asks you to solve for a, we [URL='https://www.mathcelebrity.com/1unk.php?num=4%28a-44%29%3D64&pl=Solve']type this equation into our search engine[/URL] and we get:
a = [B]60[/B]
A 50-foot pole and a 70-foot pole are 30 feet apart. If you were to run a line between the tops of tA 50-foot pole and a 70-foot pole are 30 feet apart. If you were to run a line between the tops of the two poles, what is the minimum length of cord you would need?
The difference between the 70 foot and 50 foot pole is:
70 - 50 = 20 foot height difference.
So we have a right triangle, with a height of 20, base of 30. We want to know the hypotenuse.
Using our [URL='https://www.mathcelebrity.com/pythag.php?side1input=20&side2input=30&hypinput=&pl=Solve+Missing+Side']Pythagorean theorem calculator to solve for hypotenuse[/URL], we get:
hypotenuse = [B]36.06 feet[/B]
A car worth $43,000 brand new, depreciates at a rate of $2000 per year. What is the formula that desA car worth $43,000 brand new, depreciates at a rate of $2000 per year. What is the formula that describes the relationship between the value of the car (C) and the time after it has been purchased (t)?
Let t be the number of years since purchase. Depreciation means the value decreases, so we have:
[B]C = 43000 - 2000t[/B]
A card is drawn from a pack of 52 cards. The probability that the card drawn is a red card isA card is drawn from a pack of 52 cards. The probability that the card drawn is a red card is
The deck is split evenly between red and black cards.
So we have 52/2 = 26 red cards
P(Red) = # of Red Cards / Total Deck Cards
P(Red) = 26/52
We can simplify this fraction. [URL='https://www.mathcelebrity.com/fraction.php?frac1=26%2F52&frac2=3%2F8&pl=Simplify']Using our fraction calculator[/URL], we get:
P(Red) = [B]1/2 or 0.5[/B]
A certain type of an elephant would weigh 8 to 12 tons. How many pounds would it weigh?A certain type of an elephant would weigh 8 to 12 tons. How many pounds would it weigh?
1 ton = 2000 pounds.
8 tons = 8 * 2000 = 16000 pounds
12 tons = 12 * 20000 = 24000 pounds
So the elephant weighs between 16000 and 24000 pounds
A financial analyst computed the ROI for all companies listed on the NYSE. She found that the mean oA financial analyst computed the ROI for all companies listed on the NYSE. She found that the mean of this distribution was 10% with standard deviation of 5%. She is interested in examining further those companies whose ROI is between 14% and 16% of the approximately 1,500 companies listed on the exchange, how many are of interest of her?
First, use our [URL='http://www.mathcelebrity.com/zscore.php?z=p%280.14%3Cz%3C0.16%29&pl=Calculate+Probability']z-score calculator[/URL] to get P(0.14 < z < 0.16) = 0.007889
Divide that by 2 for two-tail test to get0.003944729
Use the NORMSINV(0.003944729) in Excel to get the Z value of 2.66
Therefore, the companies of interest are 2.66 * 1500 * 0.10 = [B]399[/B]
A holiday in Florida costs $876. A holiday in Bali costs $394. How much more expensive is the FloridA holiday in Florida costs $876. A holiday in Bali costs $394. How much more expensive is the Florida holiday?
We want the difference between Florida holiday costs and Bali holiday costs:
$876 - $394 = [B]$482[/B]
A is the set of odd integers between 4 and 12A is the set of odd integers between 4 and 12
Let A be the set of odd numbers between 4 and 12:
[B]A = {5, 7, 9, 11}[/B]
A Middleweight UFC fighter weighs between 170 lbs and 185 lbs.A Middleweight UFC fighter weighs between 170 lbs and 185 lbs.
Let w be the UFC fighter's weight:
We have a compound inequality.
Right side includes 185 lbs. because between means includes 185lbs.
Left side includes 170 lbs. because between means includes 17lb0s
[B]170 <= w <= 185[/B]
A parabola has a Vertex at (4,-2) and a Focus at (6,-2). Find the equation of the parabolaA parabola has a Vertex at (4,-2) and a Focus at (6,-2). Find the equation of the parabola and the lotus rectum.
Equation of a parabola given the vertex and focus is:
([I]x[/I] – [I]h[/I])^2 = 4[I]p[/I]([I]y[/I] – [I]k[/I])
The vertex (h, k) is 4, -2
The distance is p, and since the y coordinates of -2 are equal, the distance is 6 - 4 = 2.
So p = 2
Our parabola equation becomes:
(x - 4)^2 = 4(2)(y - -2)
[B](x - 4)^2 = 8(y + 2)[/B]
Latus rectum of a parabola is 4p, where p is the distance between the vertex and the focus
LR = 4p
LR = 4(2)
[B]LR = 8[/B]
A professor assumed there was a correlation between the amount of hours people were expose to sunligA professor assumed there was a correlation between the amount of hours people were expose to sunlight and their blood vitamin D level. The null hypothesis was that the population correlation was__
a. Positive 1.0
b. Negative 1.0
c. Zero
d. Positive 0.50
[B]c. Zero[/B]
Reason: Since the professor wanted to assume a correlation (either positive = 1.0 or negative = -1.0), then we take the other side of that assumption for our null hypothesis and say that there is no correlation (Zero)
A random sample of 25 customers was chosen in CCP MiniMart between 3:00 and 4:00 PM on a Friday afteA random sample of 25 customers was chosen in CCP MiniMart between 3:00 and 4:00 PM on a Friday afternoon. The frequency distribution below shows the distribution for checkout time (in minutes).
Checkout Time (in minutes) | Frequency | Relative Frequency
1.0 - 1.9 | 2 | ?
2.0 - 2.9 | 8 | ?
3.0 - 3.9 | ? | ?
4.0 - 5.9 | 5 | ?
Total | 25 | ?
(a) Complete the frequency table with frequency and relative frequency.
(b) What percentage of the checkout times was less than 3 minutes?
(c)In what class interval must the median lie? Explain your answer.
(d) Assume that the largest observation in this dataset is 5.8. Suppose this observation were incorrectly recorded as 8.5 instead of 5.8. Will the mean increase, decrease, or remain the same? Will the median increase, decrease or remain the same? Why?
(a)
[B]Checkout Time (in minutes) | Frequency | Relative Frequency
1.0 - 1.9 | 2 | 2/25
2.0 - 2.9 | 8 | 8/25
3.0 - 3.9 | 10 (since 25 - 5 + 8 + 2) = 10 | 10/25
4.0 - 5.9 | 5 | 5/25
Total | 25 | ?[/B]
(b) (2 + 8)/25 = 10/25 = [B]40%[/B]
c) [B]3.0 - 3.9[/B] since 2 + 8 + 10 + 5 = 25 and 13 is the middle value which occurs in the 3.0 - 3.9 interval
(d) [B]Mean increases[/B] since it's a higher value than usual. Median would not change as the median is the most frequent distribution and assuming the 5.8 is only recorded once.
A random sample of 40 adults with no children under the age of 18 years results in a mean daily leisA random sample of 40 adults with no children under the age of 18 years results in a mean daily leisure time of 5.22 hours, with a standard deviation of 2.31 hours. A random sample of 40 adults with children under the age of 18 results in a mean daily leisure time of 4.44 hours, with a standard deviation of 1.74 hours. Construct and interpret a 90% confidence interval for the mean difference in leisure time between adults with no children and adults with children left parenthesis mu 1 minus mu 2 right parenthesis (μ1 - μ2).
Using our confidence interval for [URL='http://www.mathcelebrity.com/meandiffconf.php?n1=+40&xbar1=+5.22&stdev1=+2.31&n2=+40&xbar2=+4.44&stdev2=1.74&conf=+90&pl=Mean+Diff+Conf.+Interval+%28Large+Sample%29']difference of means calculator[/URL], we get:
[B]0.0278 < μ1 - μ2 < 1.5322[/B]
A random sample of 40 adults with no children under the age of 18 years results in a mean daily leisA random sample of 40 adults with no children under the age of 18 years results in a mean daily leisure time of 5.22 hours, with a standard deviation of 2.31 hours. A random sample of 40 adults with children under the age of 18 results in a mean daily leisure time of 4.29 hours, with a standard deviation of 1.58 hours. Construct and interpret a 90% confidence interval for the mean difference in leisure time between adults with no children and adults with children (u1 - u2)
What is the interpretation of this confidence interval?
A. There is 90% confidence that the difference of the means is in the interval. Conclude that there is insufficient evidence of a significant difference in the number of leisure hours
B. There is a 90% probability that the difference of the means is in the interval. Conclude that there is a significant difference in the number of leisure hours
C. There is 90% confidence that the difference of the means is in the interval. Conclude that there is a significant difference in the number of leisure hours
D. There is a 90% probability that the difference of the means is in the interval. Conclude that there is insufficient evidence of a significant difference in the number of leisure hours
0.2021 < u1 - u2 < 1.6579 using our [URL='http://www.mathcelebrity.com/meandiffconf.php?n1=+40&xbar1=+5.22&stdev1=2.31&n2=40&xbar2=4.29&stdev2=1.58&conf=+90&pl=Mean+Diff+Conf.+Interval+%28Large+Sample%29']difference of means confidence interval calculator[/URL]
[B]Choice D
There is a 90% probability that the difference of the means is in the interval. Conclude that there is insufficient evidence of a significant difference in the number of leisure hours[/B]
A researcher posed a null hypothesis that there was no significant difference between boys and girlsA researcher posed a null hypothesis that there was no significant difference between boys and girls on a standard memory test. He randomly sampled 100 girls and 120 boys in a community and gave them the standard memory test. The mean score for girls was 70 and the standard deviation of mean was 5.0. The mean score for boys was 65 and the standard deviation of mean was 6.0. What's the absolute value of the difference between means?
|70 -65| = |5| = 5
A researcher posed a null hypothesis that there was no significant difference between boys and girlsA researcher posed a null hypothesis that there was no significant difference between boys and girls on a standard memory test. He randomly sampled 100 girls and 100 boys in a community and gave them the standard memory test. The mean score for girls was 70 and the standard deviation of mean was 5.0. The mean score for boys was 65 and the standard deviation of mean was 5.0. What is the standard error of the difference in means?
[B]0.707106781187[/B] using our [URL='http://www.mathcelebrity.com/meandiffconf.php?n1=+100&xbar1=70&stdev1=5&n2=+100&xbar2=65&stdev2=5&conf=+99&pl=Hypothesis+Test']difference of means calculator[/URL]
A researcher posed a null hypothesis that there was no significant difference between boys and girlsA researcher posed a null hypothesis that there was no significant difference between boys and girls on a standard memory test. He randomly sampled 100 girls and 100 boys in a community and gave them the standard memory test. The mean score for girls was 70 and the standard deviation of mean was 5.0. The mean score for boys was 65 and the standard deviation of mean was 5.0. What's the t-value (two-tailed) for the null hypothesis that boys and girls have the same test scores?
t = 7.07106781187 using our [URL='http://www.mathcelebrity.com/meandiffconf.php?n1=+100&xbar1=70&stdev1=5&n2=+100&xbar2=65&stdev2=5&conf=+99&pl=Hypothesis+Test']difference of means calculator[/URL]
A typical adult has an average IQ score of 105 with a standard deviation of 20. If 20 randomly selecA typical adult has an average IQ score of 105 with a standard deviation of 20. If 20 randomly selected adults are given an IQ test, what is the probability that the sample mean scores will be between 85 and 125 points?
For x = 125, our z-score and probability is seen [URL='http://www.mathcelebrity.com/probnormdist.php?xone=+125&mean=+105&stdev=+20&n=+1&pl=P%28X+%3C+Z%29']here[/URL]
Z = 1
P(x < 1) = 0.841345
For x = 85, our z-score and probability is seen [URL='http://www.mathcelebrity.com/probnormdist.php?xone=+85&mean=+105&stdev=+20&n=+1&pl=P%28X+%3C+Z%29']here[/URL]
Z = -1
P(x < -1) = 0.158655
So what we want is the probability between these values:
0.841345 - 0.158655 = [B]0.68269[/B]
A young dad, who was a star football player in college, set up a miniature football field for his fiA young dad, who was a star football player in college, set up a miniature football field for his five-year-old young daughter, who was already displaying an unusual talent for place-kicking. At each end of the mini-field, he set up goal posts so she could practice kicking extra points and field goals. He was very careful to ensure the goalposts were each straight up and down and that the crossbars were level. On each set, the crossbar was six feet long, and a string from the top of each goalpost to the midpoint between them on the ground measured five feet. How tall were the goalposts? How do you know this to be true?
The center of each crossbar is 3 feet from each goalpost. We get this by taking half of 6, since midpoint means halfway.
Imagine a third post midway between the two goal posts. It has the same height as the two goalposts.
From the center post, the string from the top of a goalpost to the base of the center post, and half the crossbar form and right triangle with hypotenuse 5 feet and one leg 3 feet.
[URL='https://www.mathcelebrity.com/pythag.php?side1input=&side2input=3&hypinput=5&pl=Solve+Missing+Side']Using the Pythagorean Theorem[/URL], the other leg -- the height of each post -- is 4 feet.
Absolute DifferenceFree Absolute Difference Calculator - Calculates the absolute difference between 2 numbers. Also known as positive difference
An indoor water park has two giant buckets that slowly fill with 1000 gallons of water before dumpinAn indoor water park has two giant buckets that slowly fill with 1000 gallons of water before dumping it on the people below. One bucket dumps water every 18 minutes. The other bucket dumps water every 21 minutes. It is currently 1:15 P.M. and both buckets dumped water 5 minutes ago. Find the next two times that both buckets dump water at the same time.
We want to find the Least Common Multiple between 18 minutes and 21 minutes. This shows us when both bucket dumping cycles happen simultaneously. So we[URL='https://www.mathcelebrity.com/gcflcm.php?num1=18&num2=21&num3=&pl=GCF+and+LCM'] type in LCM(18,21) into our search engine and we get[/URL]:
LCM(18, 21) = 126
This means, in 126 minutes, both buckets will dump water. Since 60 minutes is in an hour, we find out how many full hours we have. To find the full hours and remainder, we [URL='https://www.mathcelebrity.com/modulus.php?num=126mod60&pl=Calculate+Modulus']type in 126 mod 60[/URL] into our search engine and we get:
6. This means 126 minutes is 2 hours and 6 minutes.
Find the next bucket dumping time:
[LIST=1]
[*]We start at 1:15 PM
[*]Add 2 hours and we get 3:15 PM
[*]Add 6 minutes and we get [B]3:21 PM[/B]
[/LIST]
Ana has 24 carrots, 12 cucumbers, and 36 radishes. She wants to make identical vegetable baskets usiAna has 24 carrots, 12 cucumbers, and 36 radishes. She wants to make identical vegetable baskets using all of the vegetables. What is the greatest number of baskets she can make
The key to solving this problem is asking what is the common factor between the 3 numbers. We want the greatest common factor or GCF
[URL='https://www.mathcelebrity.com/gcflcm.php?num1=12&num2=24&num3=36&pl=GCF']GCF(12, 24, 36) [/URL]= [B]12[/B]
We divide up our 12 baskets into carrots, cucumbers, and radishes. Each basket of the 12 baskets has the following:
[LIST=1]
[*]12 cucumbers / GCF of 12 = [B]1 cucumber per basket[/B]
[*]24 carrots / GCF of 12 = [B]2 carrots per basket[/B]
[*]36 radishes / GCF of 12 = [B]3 radishes per basket[/B]
[/LIST]
[B][MEDIA=youtube]D1KTOP0h2P4[/MEDIA][/B]
Ana's height is strictly between 63 and 66 inches. Write a symbolic inequality to represent this sceAna's height is strictly between 63 and 66 inches. Write a symbolic inequality to represent this scenario. let h be height
[B]63 < h < 66
[/B]
You can also type [I][URL='https://www.mathcelebrity.com/algexpress.php?num=between63and66&pl=Write+Expression']between 63 and 66[/URL][/I] in our search engine.
April, May and June have 90 sweets between them. May has three-quarters of the number of sweets thatApril, May and June have 90 sweets between them. May has three-quarters of the number of sweets that June has. April has two-thirds of the number of sweets that May has. How many sweets does June have?
Let the April sweets be a.
Let the May sweets be m.
Let the June sweets be j.
We're given the following equations:
[LIST=1]
[*]m = 3j/4
[*]a = 2m/3
[*]a + j + m = 90
[/LIST]
Cross multiply #2;
3a = 2m
Dividing each side by 2, we get;
m = 3a/2
Since m = 3j/4 from equation #1, we have:
3j/4 = 3a/2
Cross multiply:
6j = 12a
Divide each side by 12:
a = j/2
So we have:
[LIST=1]
[*]m = 3j/4
[*]a = j/2
[*]a + j + m = 90
[/LIST]
Now substitute equation 1 and 2 into equation 3:
j/2 + j + 3j/4 = 90
Multiply each side by 4 to eliminate fractions:
2j + 4j + 3j = 360
To solve this equation for j, we [URL='https://www.mathcelebrity.com/1unk.php?num=2j%2B4j%2B3j%3D360&pl=Solve']type it in our search engine[/URL] and we get:
j = [B]40[/B]
Area ConversionsFree Area Conversions Calculator - This calculator converts between the following area measurements:
acre
hectare
square inch
square foot
square yard
square mile
square millimeter
square meter
square kilometer
As the sample size increases, we assume:As the sample size increases, we assume:
a. α increases
b. β increases
c. The probability of rejecting a hypothesis increases
d. Power increases
[B]d. Power increases[/B]
[LIST]
[*]Power increases if the standard deviation is smaller.
[*]If the difference between the means is bigger, the power is bigger.
[*]Sample size also increases power
[/LIST]
Assuming a standard 52-card deck, what's the probability of dealing three eights in a row when the cAssuming a standard 52-card deck, what's the probability of dealing three eights in a row when the cards are returned and the deck is shuffled between each draw?
There are four (8's) in a standard 52 card deck. The probability of drawing an 8 is:
4/52
[URL='https://www.mathcelebrity.com/fraction.php?frac1=4%2F52&frac2=3%2F8&pl=Simplify']Using our fraction simplifier[/URL], we get:
1/13
Now, with each draw, we replace the deck. So each draw of an 8 has a 1/13 probability. And since each of the three draws is independent, we multiply each probability:
1/13 * 1/13 * 1/13 = [B]1/2197 or 0.00045516613[/B]
Bitwise OperationsFree Bitwise Operations Calculator - Performs bitwise operations between two decimal or binary numbers:
* Bitwise OR
* Bitwise AND
* Bitwise XOR
Also performs Bitwise NOT on 1 number
Bob weighs between 125 and 135Bob weighs between 125 and 135
Let w be Bob's weight. Between means includes, so we have a compound inequality:
[B]125 <= w <= 135[/B]
Bond Flat Price-Accrued Coupon-Market PriceFree Bond Flat Price-Accrued Coupon-Market Price Calculator - Calculates the flat price, accrued coupon, and market price for a bond between valuation dates using the following methods:
1) Theoretical Method
2) Practical Method
3) Semi-Theoretical Method
Carl is taking a math test. There are 10 questions which take 30 seconds each; 15 questions which taCarl is taking a math test. There are 10 questions which take 30 seconds each; 15 questions which take 40 seconds each; and 12 questions which take 2 minutes each. Carl pauses for 5 seconds between questions. In addition, he sharpens his pencil twice, which takes 20 seconds each time. The test begins promptly at 10:00 am. When Carl hands in his completed test, what time is it?
[U]10 Questions:[/U]
[LIST]
[*]30 seconds each x 10 questions = 5 minutes
[*]10 pauses between questions x 5 seconds per question = 50 seconds
[/LIST]
[U]15 Questions[/U]
[LIST]
[*]40 seconds each x 15 questions = 600 seconds, or 10 minutes
[*]15 pauses between questions x 5 seconds per question = 75 seconds, or 1 minute, 15 seconds
[/LIST]
[U]12 Questions[/U]
[LIST]
[*]2 minutes x 12 questions = 24 minutes
[*]12 pauses x 5 seconds per question = 60 seconds, or 1 minute
[/LIST]
[U]2 Pencil Sharpenings[/U]
[LIST]
[*]2 pencil sharpening x 20 seconds each = 40 seconds
[/LIST]
[U]Total Time[/U]
5 minutes, 50 seconds
11 minutes, 15 seconds
25 minutes
40 seconds
41 minutes and 105 seconds
But 105 seconds is 1 minute, 45 seconds.
So we have 41 minutes, 45 seconds
Therefore, it's [B]10:41[/B]
CHEBYSHEVS THEOREM TELLS US THAT WHAT PERCENTAGE LIES BETWEEN 2.25 STANDARD DEVIATIONS?CHEBYSHEVS THEOREM TELLS US THAT WHAT PERCENTAGE LIES BETWEEN 2.25 STANDARD DEVIATIONS?
Using our [URL='http://www.mathcelebrity.com/chebyshev.php?pl=probability&k=2.25&probk=0.75']Chebyshevs Theorem calculator[/URL], we get:
P(X - u| < kσ) >= [B]0.802469[/B]
Clock AngleFree Clock Angle Calculator - Calculate the angle on a clock between the hour and minute hands or how many times on the clock form an angle of (x°) between the minute and hour hand (backwards and forwards). Clock Angle Calculator
Coin Denomination ConversionsFree Coin Denomination Conversions Calculator - This caculator converts between the following coin denominations:
* Penny
* Nickel
* Dime
* Quarter
* Half-Dollar
* Dollar
Compute a 75% Chebyshev interval around the mean for x values and also for y values.Compute a 75% Chebyshev interval around the mean for [I]x[/I] values and also for [I]y[/I] values.
[B][U]Grid E: [I]x[/I] variable[/U][/B]
11.92 34.86 26.72 24.50 38.93 8.59 29.31
23.39 24.13 30.05 21.54 35.97 7.48 35.97
[B][U]Grid H: [I]y[/I] variable[/U][/B]
27.86 13.29 33.03 44.31 16.58 42.43
39.61 25.51 39.14 16.58 47.13 14.70 57.47 34.44
According to Chebyshev's Theorem,
[1 - (1/k^2)] proportion of values will fall between Mean +/- (k*SD)
k in this case equal to z
z = (X-Mean)/SD
X = Mean + (z*SD)
1 - 1/k^2 = 0.75
- 1/k^2 = 0.75 - 1= - 0.25
1/k^2 = 0.25
k^2 = 1/0.25
k^2 = 4
k = 2
Therefore, z = k = 2
First, [URL='http://www.mathcelebrity.com/statbasic.php?num1=11.92%2C34.86%2C26.72%2C24.50%2C38.93%2C8.59%2C29.31%2C23.39%2C24.13%2C30.05%2C21.54%2C35.97%2C7.48%2C35.97&num2=+0.2%2C0.4%2C0.6%2C0.8%2C0.9&pl=Number+Set+Basics']determine the mean and standard deviation of x[/URL]
Mean(x) = 25.24
SD(x) = 9.7873
Required Interval for x is:
Mean - (z * SD) < X < Mean + (z * SD)
25.24 - (2 * 9.7873) < X < 25.24 - (2 * 9.7873)
25.24 - 19.5746 < X < 25.24 + 19.5746
5.6654 < X < 44.8146
Next, [URL='http://www.mathcelebrity.com/statbasic.php?num1=27.86%2C13.29%2C33.03%2C44.31%2C16.58%2C42.43%2C39.61%2C25.51%2C39.14%2C16.58%2C47.13%2C14.70%2C57.47%2C34.44&num2=+0.2%2C0.4%2C0.6%2C0.8%2C0.9&pl=Number+Set+Basics']determine the mean and standard deviation of y[/URL]
Mean(y) = 32.29
SD(y) = 9.7873
Required Interval for y is:
Mean - (z * SD) < Y < Mean + (z * SD)
32.29 - (2 * 13.1932) < Y < 32.29 - (2 * 13.1932)
32.29 - 26.3864 < Y < 32.29 + 26.3864
5.9036 < X < 58.6764
Computer Storage ConversionsFree Computer Storage Conversions Calculator - This calculator converts between the following computer storage measurements:
* byte
* kilobyte
* megabyte
* gigabyte
* terabyte
* petabyte
* exabyte
Customers arrive at the claims counter at the rate of 20 per hour (Poisson distributed). What is thCustomers arrive at the claims counter at the rate of 20 per hour (Poisson distributed). What is the probability that the arrival time between consecutive customers is less than five minutes?
Use the [I]exponential distribution[/I]
20 per 60 minutes is 1 every 3 minutes
1/λ = 3 so λ = 0.333333333
Using the [URL='http://www.mathcelebrity.com/expodist.php?x=+5&l=0.333333333&pl=CDF']exponential distribution calculator[/URL], we get F(5,0.333333333) = [B]0.811124396848[/B]
Date and Time DifferenceFree Date and Time Difference Calculator - Calculates the difference between two dates using the following methods
1) Difference in dates using year/month/day/hour/minute/second as the primary unit of time
2) Difference in dates in the form of years remaining, months remaining, days remaining, hours remaining, minutes remaining, seconds remaining.
Determine the area under the standard normal curve that lies between:Determine the area under the standard normal curve that lies between:
(a) Z = -0.38 and Z = 0.38
(b) Z = -2.66 and Z = 0
(c) Z = -1.04 and Z - 1.67
[B](a) 0.2961 using our [URL='http://www.mathcelebrity.comzscore.php?z=+p%28-0.38%3Cz%3C0.38%29&pl=Calculate+Probability']z score calculator[/URL]
(b) 0.4961 using our [URL='http://www.mathcelebrity.com/zscore.php?z=+p%28-2.66%3Cz%3C0%29&pl=Calculate+Probability']z score calculator[/URL]
(c) 0.8034 using our [URL='http://www.mathcelebrity.com/zscore.php?z=+p%28-1.04%3Cz%3C1.67%29&pl=Calculate+Probability']z score calculator[/URL][/B]
Determine whether the random variable is discrete or continuous. In each case, state the possible vDetermine whether the random variable is discrete or continuous. In each case, state the possible values of the random variable.
(a) The number of customers arriving at a bank between noon and 1:00 P.M.
(i) The random variable is continuous. The possible values are x >= 0.
(ii) The random variable is discrete. The possible values are x = 0, 1, 2,...
(iii) The random variable is continuous. The possible values are x = 0, 1, 2,...
(iv) The random variable is discrete. The possible values are x >= 0.
(b) The amount of snowfall
(i) The random variable is continuous. The possible values are s = 0, 1, 2,...
(ii) The random variable is discrete. The possible values are s >= 0.
(iii) The random variable is discrete. The possible values are s = 0, 1, 2,...
(iv) The random variable is continuous. The possible values are s >= 0.
[B](a) (ii) The random variable is discrete. The possible values are x = 0, 1, 2,...
Discrete variables are limited in the values they can take between 9 and ∞
(b) (iv) The random variable is continuous. The possible values are s >= 0. Snowfall can be a decimal and can vary between 0 and ∞[/B]
difference between 2 positive numbers is 3 and the sum of their squares is 117difference between 2 positive numbers is 3 and the sum of their squares is 117
Declare variables for each of the two numbers:
[LIST]
[*]Let the first variable be x
[*]Let the second variable be y
[/LIST]
We're given 2 equations:
[LIST=1]
[*]x - y = 3
[*]x^2 + y^2 = 117
[/LIST]
Rewrite equation (1) in terms of x by adding y to each side:
[LIST=1]
[*]x = y + 3
[*]x^2 + y^2 = 117
[/LIST]
Substitute equation (1) into equation (2) for x:
(y + 3)^2 + y^2 = 117
Evaluate and simplify:
y^2 + 3y + 3y + 9 + y^2 = 117
Combine like terms:
2y^2 + 6y + 9 = 117
Subtract 117 from each side:
2y^2 + 6y + 9 - 117 = 117 - 117
2y^2 + 6y - 108 = 0
This is a quadratic equation:
Solve the quadratic equation 2y2+6y-108 = 0
With the standard form of ax2 + bx + c, we have our a, b, and c values:
a = 2, b = 6, c = -108
Solve the quadratic equation 2y^2 + 6y - 108 = 0
The quadratic formula is denoted below:
y = -b ± sqrt(b^2 - 4ac)/2a
[U]Step 1 - calculate negative b:[/U]
-b = -(6)
-b = -6
[U]Step 2 - calculate the discriminant Δ:[/U]
Δ = b2 - 4ac:
Δ = 62 - 4 x 2 x -108
Δ = 36 - -864
Δ = 900 <--- Discriminant
Since Δ is greater than zero, we can expect two real and unequal roots.
[U]Step 3 - take the square root of the discriminant Δ:[/U]
√Δ = √(900)
√Δ = 30
[U]Step 4 - find numerator 1 which is -b + the square root of the Discriminant:[/U]
Numerator 1 = -b + √Δ
Numerator 1 = -6 + 30
Numerator 1 = 24
[U]Step 5 - find numerator 2 which is -b - the square root of the Discriminant:[/U]
Numerator 2 = -b - √Δ
Numerator 2 = -6 - 30
Numerator 2 = -36
[U]Step 6 - calculate your denominator which is 2a:[/U]
Denominator = 2 * a
Denominator = 2 * 2
Denominator = 4
[U]Step 7 - you have everything you need to solve. Find solutions:[/U]
Solution 1 = Numerator 1/Denominator
Solution 1 = 24/4
Solution 1 = 6
Solution 2 = Numerator 2/Denominator
Solution 2 = -36/4
Solution 2 = -9
[U]As a solution set, our answers would be:[/U]
(Solution 1, Solution 2) = (6, -9)
Since one of the solutions is not positive and the problem asks for 2 positive number, this problem has no solution
Difference between 23 and y is 12Difference between 23 and y
23 - y
Is, means equal to, so we set 23 - y equal to 12
[B]23 - y = 12
[/B]
If you need to solve this algebraic expression, use our [URL='http://www.mathcelebrity.com/1unk.php?num=23-y%3D12&pl=Solve']equation calculator[/URL]:
[B]y = 11[/B]
distance between -2 and 9 on the number linedistance between -2 and 9 on the number line
Distance on the number line is the absolute value of the difference:
D = |9 - -2|
D = |11|
D = [B]11[/B]
Dylans mother tells Dylan he must spend less time playing electronic games. On the weekends he spendDylans mother tells Dylan he must spend less time playing electronic games. On the weekends he spends 9.5 hours playing electronic games. If he plays between 13 and 19 hours each week, how many hours does he play games on weekdays?
Let x equal the number of hours Dylan plays electronic games per week.
[U]Set up our inequality:[/U]
13 <= x <= 19
[U]To see how much he plays during weekdays, subtract off the weekend time[/U]
13 - 9.5 <= x <= 19 - 9.5
[B]3.5 <= x <= 9.5[/B]
Edna plans to treat her boyfriend Curt to dinner for his birthday. The costs of their date options aEdna plans to treat her boyfriend Curt to dinner for his birthday. The costs of their date options are listed next to each possible choice. Edna plans to allow Curt to choose whether they will eat Mexican food ($25), Chinese food ($15), or Italian food ($30). Next, they will go bowling ($20), go to the movies ($30) or go to a museum ($10). Edna also is deciding between a new wallet ($12) and a cell phone case ($20) as possible gift options for Curt. What is the maximum cost of this date?
Edna has 3 phases of the date:
[LIST=1]
[*]Dinner
[*]Event after dinner
[*]Gift Option
[/LIST]
In order to calculate the maximum cost of the date, we take the maximum cost option of all 3 date phases:
[LIST=1]
[*]Dinner - Max price is Italian food at $30
[*]Event after dinner - Max price is movies at $30
[*]Gift Option - Max price option is the cell phone cast at $20
[/LIST]
Add all those up, we get: $30 + $30 + $20 = [B]$80[/B]
Elapsed TimeFree Elapsed Time Calculator - This determines the elapsed time between two clock readings.
Estimate a 15% tip on a dinner bell of $49.76 by first round the bill amount to the nearest $10Estimate a 15% tip on a dinner bell of $49.76 by first round the bill amount to the nearest $10.
Round the bill to the nearest $10
[LIST]
[*]$49.76 is in between ($40, $50)
[*]1/2 of that interval is (40 + 50)/2 = 90/2 = 45
[*]Since $49.76 is greater than or equal to 45, we round up to $50
[/LIST]
Add a 15% tip
50(1 + 0.15) = 50 + 7.50 = [B]$57.50[/B]
Explain the relationship between "squaring" a number and finding the "square root" of a number. UseExplain the relationship between "squaring" a number and finding the "square root" of a number. Use an example to further explain your answer.
Squaring a number means raising it to the power of 2
The square root of a number [I]undoes[/I] a square of a number.
So square root of x^2 is x
x squared is x^2
Let x = 5.
x squared = 5^2 = 25
Square root of 25 = square root of 5^2 = 5
Factors of 36 between 2 and 12Factors of 36 between 2 and 12
We type in [I][URL='https://www.mathcelebrity.com/factoriz.php?num=36&pl=Show+Factorization']factors of 36[/URL][/I] into our search engine and we get:
{1, 2, 3, 4, 6, 9, 12, 18, 36}
The problem asks for factors of 36 between 2 and 12:
Between does not mean inclusive, so we have anything greater than 2 and less than 12:
[B]{3, 4, 6, 9}[/B]
find the difference between a mountain with an altitude of 1,684 feet above sea level and a valleyfind the difference between a mountain with an altitude of 1,684 feet above sea level and a valley 216 feet below sea level.
Below sea level is the same as being on the opposite side of zero on the number line. To get the difference, we do the following:
1,684 - (-216)
Since subtracting a negative is a positive, we have:
1,684 + 216
[B]1,900 feet[/B]
Find the distance between (1,2,3) and (7,5,5)[URL='https://www.mathcelebrity.com/3dist.php?xone=1&yone=2&zone=3&xtwo=7&ytwo=5&ztwo=5&pl=Distance+between+3-D+points']Use our distance calculator[/URL]
[MEDIA=youtube]BbU23Cz1nAE[/MEDIA]
Find the distance between the points (10,7) and (6,10)Find the distance between the points (10,7) and (6,10).
[URL='https://www.mathcelebrity.com/slope.php?xone=10&yone=7&slope=+2%2F5&xtwo=6&ytwo=10&pl=You+entered+2+points']Using our two-points calculator[/URL], we get a distance of [B]5[/B].
Find the last digit of 4^2081 no calculatorFind the last digit of 4^2081 no calculator
4^1= 4
4^2 = 16
4^3 = 64
4^4 = 256
4^5 = 1024
4^6 = 4096
Notice this pattern alternates between odd exponent powers with the result ending in 4 and even exponent powers with the result ending in 6.
Since 2081 is odd, the answer is [B]4.
[MEDIA=youtube]ueBWAW4XW4Q[/MEDIA][/B]
Foster is centering a photo that is 9/1/2 inches wide on a scrapbook pages that is 10 inches wide. HFoster is centering a photo that is 9/1/2 inches wide on a scrapbook pages that is 10 inches wide. How far from each side of the pages should he put the picture? Enter your answer as a mixed number.
First, determine your margins, which is the difference between the width and photo width, divided by 2.
10 - 9 & 1/2 = 1/2
1/2 / 2 = [B]1/4[/B]
Fractions and Mixed NumbersFree Fractions and Mixed Numbers Calculator - Given (improper fractions, proper fraction, mixed numbers, or whole numbers), this performs the following operations:
* Addition (Adding)
* Subtraction (Subtracting)
* Positive Difference (Absolute Value of the Difference)
* Multiplication (Multiplying)
* Division (Dividing: complex fraction division is included)
* Compare Fractions
* Simplifying of proper and improper fractions as well as mixed numbers. Fractions will be reduced down as far as possible (Reducing Fractions).
* Reciprocal of a Fraction
* Find all fractions between two fractions
* reduce a fraction
Frequency ConversionsFree Frequency Conversions Calculator - Converts between the following frequencies:
hertz
millihertz
kilohertz
megahertz
gigahertz
terahertz
rps
rpm
rph
Gravitational ForceFree Gravitational Force Calculator - Using Sir Isaac Newtons Law of Gravitational Force, this calculator determines the force between two objects with mass in kilograms at a distance apart in meters using the constant of gravity.
He charges $1.50 per delivery and then $2 per km he has to drive to get from his kitchen to the deliHe charges $1.50 per delivery and then $2 per km he has to drive to get from his kitchen to the delivery address. Write an equation that can be used to calculate the delivery price and the distance between the kitchen and the delivery address. Use your equation to calculate the total cost to deliver to someone 2.4km away
Let k be the number of kilometers between the kitchen and delivery address. Our Delivery equation D(k) is:
[B]D(k) = 2k + 1.50[/B]
The problem wants to know D(2.4):
D(2.4) = 2(2.4) + 1.50
D(2.4) = 4.8 + 1.50
D(2.4) = [B]$6.30[/B]
heat loss of a glass window varies jointly as the window's area and the difference between the outsiheat loss of a glass window varies jointly as the window's area and the difference between the outside and the inside temperature. a window 6 feet wide by 3 feet long loses 1,320 btu per hour when the temperature outside is 22 degree colder than the temperature inside.
Find the heat loss through a glass window that is 3 feet wide by 5 feet long when the temperature outside is 9 degree cooler than the temperature inside.
Find k of the equation:
6*3*22*k = 1320
396k = 1,320
k = 3.33333 [URL='https://www.mathcelebrity.com/1unk.php?num=396k%3D1320&pl=Solve']per our equation solver[/URL]
Now, find the heat loss for a 3x5 window when the temperature is 9 degrees cooler than the temperature inside:
3*5*9*3.333333 = [B]450 btu per hour[/B]
How many degrees is an acute angleHow many degrees is an acute angle
An acute angle is an angle between 0 and less than 90 degrees:
[B]0 <= a < 90[/B]
How many of the numbers between 20 and 40 are prime numbers?[SIZE=4]How many of the numbers between 20 and 40 are prime numbers?
A) 3
B) 4
C) 5
D) 6
E) 7
Recall that a prime number is a number that only has itself and 1 as a divisor.
[/SIZE]
[LIST]
[*][SIZE=4]Remove all the evens since the are divisible by 2 (20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40)[/SIZE]
[*][SIZE=4]Remove all the remaining numbers divisible by 3 (21, 24, 27, 30, 33, 36, 39)[/SIZE]
[*][SIZE=4]Remove all the remaining numbers divisible by 5 (25, 35)[/SIZE]
[/LIST]
[SIZE=4]We're left with ([B]23, 29, 31, 37[/B])
This is 4 numbers which is answer [B]B[/B][/SIZE]
How many palindromes are between 700 and 800?How many palindromes are between 700 and 800?
Numeric palindromes are numbers which read the same backwards and forwards. In this case, the number has to start and end with 7.
[LIST=1]
[*]707
[*]717
[*]727
[*]737
[*]747
[*]757
[*]767
[*]777
[*]787
[*]797
[/LIST]
There are [B]10[/B] palindromes between 700 and 800
If 3/5 of a bun is shared equally between 4 people, what fraction of the bun would each receive?If 3/5 of a bun is shared equally between 4 people, what fraction of the bun would each receive?
[URL='https://www.mathcelebrity.com/fraction.php?frac1=3%2F5&frac2=1%2F4&pl=Multiply']We divide 3/5 by 4[/URL] to get [B]3/20[/B]
If approximately 68% of the scores lie between 40.7 and 59.9 , then the approximate value of the staIf approximately 68% of the scores lie between 40.7 and 59.9 , then the approximate value of the standard deviation for the distribution, according to the empirical rule, is
The empirical rule states 68% of the values lie within 1 standard deviation of the mean. The mean is the midpoint of the interval above:
(59.9 + 40.7)/2 = 50.3
Standard deviation is the absolute value of the mean - endpoint
|59.9 - 50.3| = [B]9.6[/B]
If power is big, you can assume:If power is big, you can assume:
a. The difference between the means is more likely to be detected
b. The significance level set by the researcher must be high
c. We increase the probability of type I error
d. Your study result will be more likely to be inconclusive
[B]b. The significance level set by the researcher must be high[/B]
If the correlation between two variables is close to minus one, the association is: Strong ModerateIf the correlation between two variables is close to minus one, the association is:
Strong
Moderate
Weak
None
[B]Strong[/B] - Coefficient near +1 or -1 indicate a strong correlation
If the max time that John can spend on Client A ($20/hr) in one week is 32 hours, and the min time iIf the max time that John can spend on Client A ($20/hr) in one week is 32 hours, and the min time is 8 hours, while the max time on Client B ($14/hr) is 8 hours and the min 5 hours, what is the RANGE (max, min) of total pay he can earn in one week (40 hours)
[LIST]
[*]Client A Minimum = 20 x 8 hours = $160
[*]Client A Maximum = 20 x 32 hours = $640
[*]Client B Minimum = 14 x 5 hours = $70
[*]Client B Maximum = 14 x 8 hours = $112
[/LIST]
[U]The Total Maximum Pay is found by adding Client A Maximum and Client B Maximum[/U]
Total Maximum = Client A Maximum + Client B Maximum
Total Maximum = 640 + 112
Total Maximum = 752
[U]The Total Minimum Pay is found by adding Client A Minimum and Client B Minimum[/U]
Total Minimum = Client A Minimum + Client B Minimum
Total Minimum = 160 + 70
Total Minimum = 230
[U]The Range is the difference between the Total maximum and the Total minimum[/U]
Range(Total Maximum, Total Minimum) = Total Maximum - Total Minimum
Range(752, 230) = 752 - 230
Range(752, 230) = [B]522[/B]
In a factory that manufactures tires, a machine responsible for molding the tire has a failure rateIn a factory that manufactures tires, a machine responsible for molding the tire has a failure rate of 0.2%. If 1,000 tires are produced in a day, of which 6 are faulty, what is the difference between the experimental probability and the theoretical probability?
Theoretical probability = Failure Rate * Tires
Theoretical probability = 0.002 * 1000
Theoretical probability = 2
The experimental probability was given as 6, so the difference is:
6 - 2 = [B]4[/B]
In order to test if there is a difference between means from two populations, which of following assIn order to test if there is a difference between means from two populations, which of following assumptions are NOT required?
a. The dependent variable scores must be a continuous quantitative variable.
b. The scores in the populations are normally distributed.
c. Each value is sampled independently from each other value.
d. The two populations have similar means
[B]a and d
[/B]
[I]because b and c [U]are[/U] required[/I]
Integers BetweenFree Integers Between Calculator - This calculator determines all integers between two numbers (Decimals)
International Unit ConversionsFree International Unit Conversions Calculator - This calculator converts between the following weight measurements:
* International Units (IU)
* mcg
* mg
Irrational Numbers BetweenFree Irrational Numbers Between Calculator - This calculator determines all irrational numbers between two numbers
Jennifer is twice as old as Peter. The difference between their ages is 15. What is Peters ageJennifer is twice as old as Peter. The difference between their ages is 15. What is Peters age
Let j be Jennifer's age
Let p be Peter's age
We're given two equations:
[LIST=1]
[*]j = 2p
[*]j - p = 15
[/LIST]
Substitute equation (1) into equation (2) for j
2p - p = 15
To solve for p, we [URL='https://www.mathcelebrity.com/1unk.php?num=2p-p%3D15&pl=Solve']type this equation into our calculation engine[/URL] and we get:
p = [B]15[/B]
Joint Variation EquationsFree Joint Variation Equations Calculator - Given a joint variation (jointly proportional) of a variable between two other variables with a predefined set of conditions, this will create the joint variation equation and solve based on conditions.
Also called combined variation.
Kamille is calculating the length of diagonal on a picture board and gets a solution of the square rKamille is calculating the length of diagonal on a picture board and gets a solution of the square root of 58. She needs to buy the ribbon to put across the diagonal of the board, so she estimates that she will need at least 60 inches of ribbon to cover the diagonal. Is she correct? Explain.
[URL='https://www.mathcelebrity.com/powersq.php?num=sqrt%2858%29&pl=Calculate']The square root of 58 [/URL]has an answer between 7 and 8.
So Kamille is [B]incorrect[/B]. She needs much less than 60 inches of ribbon. She needs less than 8 inches of ribbon.
Kayla has $1500 in her bank account. She spends $150 each week. Write an equation in slope-interceptKayla has $1500 in her bank account. She spends $150 each week. Write an equation in slope-intercept form that represents the relationship between the amount in Kayla's bank account, A, and the number of weeks she has been spending, w
[LIST]
[*]Slope intercept form is written as A = mw + b
[*]m = -150, since spending is a decrease
[*]b = 1500, since this is what Kayla starts with when w = 0
[/LIST]
[B]A = -150w + 1500[/B]
Kimberly takes 4 pages of notes during each hour of class. Write an equation that shows the relationKimberly takes 4 pages of notes during each hour of class. Write an equation that shows the relationship between the time in class x and the number of pages y.
With x hours and y pages, our equation is:
[B]y = 4x [/B]
KitesFree Kites Calculator - This calculates perimeter and/or area of a kite given certain inputs such as short and long side, short and long diagonal, or angle between short and long side
Laura found a roll of fencing in her garage. She couldn't decide whether to fence in a square gardenLaura found a roll of fencing in her garage. She couldn't decide whether to fence in a square garden or a round garden with the fencing.
Laura did some calculations and found that a circular garden would give her 1380 more square feet than a square garden. How many feet of fencing were in the roll that Laura found? (Round to the nearest foot.)
Feet of fencing = n
Perimeter of square garden = n
Each side of square = n/4
Square garden's area = (n/4)^2 = n^2/16
Area of circle garden with circumference = n is:
Circumference = pi * d
n = pi * d
Divide body tissues by pi:
d = n/pi
Radius = n/2pi
Area = pi * n/2pi * n/2pi
Area = pin^2/4pi^2
Reduce by canceling pi:
n^2/4pi
n^2/4 * 3.14
n^2/12.56
The problem says that the difference between the square's area and the circle's area is equal to 1380 square feet.
Area of Circle - Area of Square = 1380
n^2/12.56 - n^2/16 = 1380
Common denominator = 200.96
(16n^2 - 12.56n^2)/200.96 = 1380
3.44n^2/200.96 = 1380
Cross multiply:
3.44n^2 = 277,324.8
n^2 = 80,617.7
n = 283.9
Nearest foot = [B]284[/B]
Let A = (-4,5) and B = (1,3) Find the distance from A to BLet A = (-4,5) and B = (1,3) Find the distance from A to B
Using our [URL='https://www.mathcelebrity.com/slope.php?xone=-4&yone=5&slope=+&xtwo=1&ytwo=3&bvalue=+&pl=You+entered+2+points']distance between two points calculator[/URL], we get:
[B]5.3852[/B]
Let U be the set of all integers between −3 and 3 (including −3 and 3). Let A={−2,0,1,3}. Find Ac. GLet U be the set of all integers between −3 and 3 (including −3 and 3). Let A={−2,0,1,3}. Find Ac. Give your answer in standard set notation
Ac is anything not in A, but in U. So we have:
Ac = [B]{-3, -1, 2}[/B]
Liam, a 19th century cowboy, carries an 1847 Colt single action 6 shooter revolver. So proficient isLiam, a 19th century cowboy, carries an 1847 Colt single action 6 shooter revolver. So proficient is he with this weapon that when he fires all 6 shots in a row, the time between the first bullet and the last is 40 seconds. How long would it take him to fire 4 shots?
We set up a proportion of shots to seconds where s is the number of seconds it takes to fire 4 shots:
6/40 = 4/s
Using our [URL='https://www.mathcelebrity.com/prop.php?num1=6&num2=4&den1=40&den2=s&propsign=%3D&pl=Calculate+missing+proportion+value']proportion calculator[/URL], we get:
s = [B]26.67[/B]
Lily needs an internet connectivity package for her firm. She has a choice between CIVISIN and GOMILily needs an internet connectivity package for her firm. She has a choice between CIVISIN and GOMI with the following monthly billing policies. Each company's monthly billing policy has an initial operating fee and charge per megabyte.
Operating Fee charge per Mb
CIVSIN 29.95 0.14
GOMI 4.95 0.39
(i) Write down a system of equations to model the above situation
(ii) At how many Mb is the monthly cost the same? What is the equal monthly cost of the two plans?
(i) Set up a cost function C(m) for CIVSIN where m is the number of megabytes used:
C(m) = charge per Mb * m + Operating Fee
[B]C(m) = 0.14m + 29.95[/B]
Set up a cost function C(m) for GOMI where m is the number of megabytes used:
C(m) = charge per Mb * m + Operating Fee
[B]C(m) = 0.39m + 4.95
[/B]
(ii) At how many Mb is the monthly cost the same?
Set both cost functions equal to each other:
0.14m + 29.95 = 0.39m + 4.95
We [URL='https://www.mathcelebrity.com/1unk.php?num=0.14m%2B29.95%3D0.39m%2B4.95&pl=Solve']type this equation into our search engine[/URL] and we get:
m = [B]100[/B]
(ii) What is the equal monthly cost of the two plans?
CIVSIN - We want C(100) from above where m = 100
C(100) = 0.14(100) + 29.95
C(100) = 14 + 29.95
C(100) = [B]43.95[/B]
GOMI - We want C(100) from above where m = 100
C(100) = 0.39(100) + 4.95
C(100) = 39 + 4.95
C(100) = [B]43.95[/B]
Line Equation-Slope-Distance-Midpoint-Y interceptFree Line Equation-Slope-Distance-Midpoint-Y intercept Calculator - Enter 2 points, and this calculates the following:
* Slope of the line (rise over run) and the line equation y = mx + b that joins the 2 points
* Midpoint of the two points
* Distance between the 2 points
* 2 remaining angles of the rignt triangle formed by the 2 points
* y intercept of the line equation
* Point-Slope Form
* Parametric Equations and Symmetric Equations
Or, if you are given a point on a line and the slope of the line including that point, this calculates the equation of that line and the y intercept of that line equation, and point-slope form.
Also allows for the entry of m and b to form the line equation
Marco takes 2 quizzes each week. Write an equation that shows the relationship between the number ofMarco takes 2 quizzes each week. Write an equation that shows the relationship between the number of weeks x and the total number of quizzes y. Write your answer as an equation with y first, followed by an equals sign.
Our total quizzes equal 2 times the number of weeks (x):
[B]y = 2x[/B]
Marginal propensity to save is 0.3. Calculate MPCMarginal propensity to save is 0.3. Calculate MPC.
MPC is Marginal Propensity to Consume. And MPS is Marginan Propensity to Save.
The relational equation between the two is:
MPC + MPS = 1
To get MPC, we have:
MPC = 1 - MPS
The problem gives us MPS = 0.3, so plug it into this modified MPC equation:
MPC = 1 - 0.3
MPC = [B]0.7[/B]
Midpoint formulaMidpoint formula
Given two points (x1, y1) and (x2, y2), the midpoint is found as the average distance between the 2 points:
[LIST]
[*]x value is: (x1 + x2)/2
[*]y value is: (y1 + y2)/2
[/LIST]
So our midpoint is:
((x1 + x2)/2, (y1 + y2)/2)
Mike works in a toy store. One week, he worked 38 hours and made $220. The next week, he received aMike works in a toy store. One week, he worked 38 hours and made $220. The next week, he received a raise, so when he worked 30 hours he made $180. How much was his raise (to the nearest cent)?
First week, Mike earns the following in hours (h)
38h = 220
h = 5.79 [URL='https://www.mathcelebrity.com/1unk.php?num=38h%3D220&pl=Solve']using our equation calculator[/URL]
We call this his old hourly salary
Next week, Mike earns the following in hours (h)
30h = 180
h = 6 [URL='https://www.mathcelebrity.com/1unk.php?num=30h%3D180&pl=Solve']using our equation calculator[/URL]
We call this his new hourly salary
His raise is the difference between his current hourly salary and his old hourly salary:
Raise = New Hourly Salary - Old Hourly Salary
Raise = 6 - 5.79
Raise = [B]$0.21[/B]
Mike got a 21 cent hourly raise
Mount McKinley in Alaska, the highest mountain in North America, is 20,320 feet above sea level. DeaMount McKinley in Alaska, the highest mountain in North America, is 20,320 feet above sea level. Death Valley, the lowest point, is 280 feet below sea level. What is the difference in height between Mount McKinley and Death Valley?
Regarding height with respect to sea level...
[LIST]
[*]Above sea level is written as positive height
[*]Below sea level is written as negative height
[/LIST]
So we have:
+20,320 - -280
+20,320 + 280
[B]20,600[/B]
Mt. Everest, the highest elevation in Asia, is 29,028 feet above sea level. The Dead Sea, the lowestMt. Everest, the highest elevation in Asia, is 29,028 feet above sea level. The Dead Sea, the lowest elevation, is 1,312 feet below sea level. What is the difference between these two elevations?
Above sea level is listed as positive (+)
Below sea level is listed as negative (-)
We have:
Difference = +29,028 - (-1312)
Difference = 29028 + 1312
[URL='https://www.mathcelebrity.com/longdiv.php?num1=29028&num2=1312&pl=Add']Difference[/URL] = [B]30,340[/B]
My rent was 800.00 a month. My landlord raised my rent to 1,240.00. What percentage did he raise mMy rent was 800.00 a month. My landlord raised my rent to 1,240.00. What percentage did he raise my rent?.
First, calculate the difference between the old and new rent:
Difference = 1,240 - 800 = 440
Percentage increase = 440/800
[URL='https://www.mathcelebrity.com/perc.php?num=440&den=800&pcheck=1&num1=16&pct1=80&pct2=70&den1=80&idpct1=10&hltype=1&idpct2=90&pct=82&decimal=+65.236&astart=12&aend=20&wp1=20&wp2=30&pl=Calculate']Type 440/800 into the search engine, and choose the percent option[/URL]
You get [B]55%[/B] increase.
n increased by the difference between 10 times n and 9n increased by the difference between 10 times n and 9
Take this algebraic expression in pieces:
[LIST]
[*]10 times n: 10n
[*]The difference between 10 times n and 9: 10n - 9
[*]n increased by the difference...: [B]n + (10n - 9)[/B]
[/LIST]
Nia is trying to decide between two possible jobs. Job A pays $2000 a month with a 2% annual raise.Nia is trying to decide between two possible jobs. Job A pays $2000 a month with a 2% annual raise. Job B pays 24,000 a year with a $500 annual raise. Write a function to represent the annual salary for Job A after x years. Write a function to represent the annual salary for Job B after x years. After how many years would Nia have a greater salary at Job A?
Nia Job A salary at time t: S(t)
$2,000 per month equals $24,000 per year.
So we have S(t) = 24,000(1.o2)^t
Nia Job B salary at time t: S(t)
$24,000 per year.
So we have S(t) = 24,000 + 500t
We want to know t when Job A salary is greater than Job B Salary:
24,000(1.o2)^t > 24,000 + 500t
Time | A | B
0 | 24000 | 24000
1 | 24480 | 24500
2 | 24969.6 | 25000
3 | 25468.99 | 25500
4 | 25978.37 | 26000
5 | 26497.94 | 26500
6 | 27027.9 | 27000
7 | 27568.46 | 27500
8 | 28119.83 | 28000
9 | 28682.22 | 28500
10 | 29255.87 | 29000
11 | 29840.98 | 29500
12 | 30437.8 | 30000
13 | 31046.56 | 30500
Normal DistributionFree Normal Distribution Calculator - Calculates the probability that a random variable is less than or greater than a value or between 2 values using the Normal Distribution z-score (z value) method (Central Limit Theorem).
Also calculates the Range of values for the 68-95-99.7 rule, or three-sigma rule, or empirical rule. Calculates z score probability
Number Line MidpointFree Number Line Midpoint Calculator - Calculates a midpoint between 2 points on a number line or finds the second endpoint if one endpoint and midpoint are given.
On July 10, the high temperature in Phoenix, Arizona, was 109°, and the high temperature in Juneau,On July 10, the high temperature in Phoenix, Arizona, was 109°, and the high temperature in Juneau, Alaska, was 63°. What was the difference between the temperature in Phoenix and the temperature in Juneau?
Difference is found by subtracting the lower temperature from the higher temperature:
[URL='https://www.mathcelebrity.com/longdiv.php?num1=109&num2=63&pl=Subtract']109 - 63 [/URL]= [B]46[/B]
One positive number is one-fifth of another number. The difference between the two numbers is 192, fOne positive number is one-fifth of another number. The difference between the two numbers is 192, find the numbers.
Let the first number be x and the second number be y. We're given two equations:
[LIST=1]
[*]x = y/5
[*]x + y = 192
[/LIST]
Substitute equation 1 into equation 2:
y/5 + y = 192
Since 1 equals 5/5, we rewrite our equation like this:
y/5 = 5y/5 = 192
We have fractions with like denominators, so we add the numerators:
(1 + 5)y/5 = 192
6y/5 = 192
[URL='https://www.mathcelebrity.com/prop.php?num1=6y&num2=192&den1=5&den2=1&propsign=%3D&pl=Calculate+missing+proportion+value']Type this equation into our search engine[/URL], and we get:
[B]y = 160[/B]
Substitute this value into equation 1:
x = 160/5
x = [B]32[/B]
Opposite Direction DistanceFree Opposite Direction Distance Calculator - Word Problem calculator to measure distance between 2 people moving in opposite directions with rate and time solved for as well
Password GeneratorFree Password Generator Calculator - This generates an alphanumeric password between a minimum and maximum character length that you specify.
Percent ErrorFree Percent Error Calculator - Percentage error is the difference between an experimental measured value and a theoretical actual value
Percentage ChangeFree Percentage Change Calculator - Calculates the percentage change between two values. Percentage Increase or Percentage Decrease
Percentage-Decimal-Fraction RelationsFree Percentage-Decimal-Fraction Relations Calculator - Calculates the relational items between a fraction, a decimal (including repeating decimal and terminating decimal), a percentage, and the numerator and denominator piece of that fraction. Also calculates the percentage change going from one number to another or the amount increase or decrease of a percentage above/below a number. Round decimals. decimals into fractions
please answer this word problemTime 1, distance apart is 105 + 85 = 190
So every hour, the distance between them is 190 * t where t is the number of hours. Set up our distance function:
D(t) = 190t
We want D(t) = 494
190t = 494
Divide each side by 190
[B]t = 2.6 hours[/B]
Point and a LineFree Point and a Line Calculator - Enter any line equation and a 2 dimensional point. The calculator will figure out if the point you entered lies on the line equation you entered. If the point does not lie on the line, the distance between the point and line will be calculated.
Points A, B, and C are collinear. Point B is between A and C. Find AB if AC=15 and BC=7.Points A, B, and C are collinear. Point B is between A and C. Find AB if AC=15 and BC=7.
Collinear means on the same line.
By segment subtraction, we have:
AB = AC - BC
AB = 15 - 7
AB = [B]8[/B]
Pressure ConversionsFree Pressure Conversions Calculator - This calculator converts between the following pressure measurements:
atmosphere
bar
dynes/cm2
in. Hg
in. water
kg/cm2
mbar
mtorr or micron Hg
Pa or N/m2
PSI or lb/in2
torr or mm Hg
q increased by the difference between 18 times q and 5q increased by the difference between 18 times q and 5
Take this algebraic expression in parts.
18 times q:
18q
The difference between 18 times q and 5 means we subtract 5 from 18q:
18q - 5
q increased by the difference between 18 times q and 5 means we add 18q - 5 to q:
q + (18q - 5)
[B]q + 18q - 5[/B]
IF we want to simplify, we group like terms:
[B]19q - 5[/B]
Rachel runs 2 miles during each track practice. Write an equation that shows the relationship betweRachel runs 2 miles during each track practice. Write an equation that shows the relationship between the practices p and the distance d.
Distance equals rate * practicdes, so we have:
[B]d = 2p[/B]
Random Number GeneratorFree Random Number Generator Calculator - This program generates (n) random numbers between a set of values you specify.
Example: Generate 5 random numbers between 0 and 100.
Rational Numbers BetweenFree Rational Numbers Between Calculator - This calculator determines all rational numbers between two numbers
Rick is taller than Luke, who is taller than Bruce. Steve is taller t Han Bruce, but not as tall asRick is taller than Luke, who is taller than Bruce. Steve is taller than Bruce, but not as tall as Rick. If Luke is 6 feet tall, do we know if Steve is taller than 6 feet?
Luke and Steve are between Rick and Bruce, but that is all we know. We don't know if Luke is taller or Steve is taller.
Answer is [B] NO[/B]
Roster form of: A = {3x-2/x are integers between 0 and 8}Roster form of: A = {3x-2/x are integers between 0 and 8}
x = 0 = Undefined since we divide by 0
x = 1: 3*1 + 2/1 = 5
x = 2: 3*2 + 2/2 = 7
x = 3: 3*3 + 2/3 = 9.66666666666667
x = 4: 3*4 + 2/4 = 12.5
x = 5: 3*5 + 2/5 = 15.4
x = 6: 3*6 + 2/6 = 18.3333333333333
x = 7: 3*7 + 2/7 = 21.2857142857143
x = 8: 3*8 + 2/8 = 24.25
[B]A = {(0, undefined), (1, 5), (2, 7), (3, 9.6667), (4, 12.5), (5, 15.4), (6, 18.3333), (7, 21.2857142857143), (8, 24.25)}[/B]
Speed ConversionsFree Speed Conversions Calculator - This converts between the following speed measurements:
* mph
* ft/s
* km/h
* m/sec
Stoichiometry ConversionFree Stoichiometry Conversion Calculator - Converts between molecules, moles, grams
Super Snack, a convenience store, charges $4.35 for a large chicken sandwich and two large colas. FoSuper Snack, a convenience store, charges $4.35 for a large chicken sandwich and two large colas. For a large chicken sandwich and a large cola, they charge $4.00. How much are the Super Snack large chicken sandwiches?
The difference between the orders is $0.35 and 1 large cola. Therefore, 1 large cola = $0.35.
And if we use the first order of one large chicken sandwich and one large cola, we get:
Large Chicken Sandwich + 0.35 = 4.35
Subtract 0.35 from each side, and we get:
Large Chicken Sandwich = $[B]4.00[/B]
Suppose that the manager of the Commerce Bank at Glassboro determines that 40% of all depositors havSuppose that the manager of the Commerce Bank at Glassboro determines that 40% of all depositors have a multiple accounts at the bank. If you, as a branch manager, select a random sample of 200 depositors, what is the probability that the sample proportion of depositors with multiple accounts is between 35% and 50%?
[URL='http://www.mathcelebrity.com/proportion_hypothesis.php?x=50&n=+100&ptype==&p=+0.4&alpha=+0.05&pl=Proportion+Hypothesis+Testing']50% proportion probability[/URL]: z = 2.04124145232
[URL='http://www.mathcelebrity.com/proportion_hypothesis.php?x=+35&n=+100&ptype==&p=+0.4&alpha=+0.05&pl=Proportion+Hypothesis+Testing']35% proportion probability[/URL]: z = -1.02062072616
Now use the [URL='http://www.mathcelebrity.com/zscore.php?z=p%28-1.02062072616
The difference between 2 numbers is 108. 6 times the smaller is equal to 2 more than the larger. Wh?The difference between 2 numbers is 108. 6 times the smaller is equal to 2 more than the larger. What are the numbers?
Let the smaller number be x. Let the larger number be y. We're given:
[LIST=1]
[*]y - x = 108
[*]6x = y + 2
[/LIST]
Rearrange (1) by adding x to each side:
[LIST=1]
[*]y = x + 108
[/LIST]
Substitute this into (2):
6x = x + 108 + 2
Combine like terms
6x = x +110
Subtract x from each side:
5x = 110
[URL='https://www.mathcelebrity.com/1unk.php?num=5x%3D110&pl=Solve']Plugging this equation into our search engine[/URL], we get:
x = [B]22[/B]
The difference between 3 times x and 4[U]3 times x:[/U]
3x
[U]The difference between 3x and 4 means we subtract:[/U]
3x - 4
the difference between 7 times a number and 9 less than a numberthe difference between 7 times a number and 9 less than a number
The phrase [I]a number[/I] means an arbitrary variable, let's call it x.
7 times a number means we multiply x by 7
7x
9 less than a number means we subtract 9 from x
x - 9
The difference between the two expressions means we subtract (x - 9) from 7x
7x - (x - 9)
Simplifying this, we have:
7x - x + 9
Grouping like terms, we get:
[B]6x + 9[/B]
The difference between a and b is 10The difference between a and b is 10.
The problem asks for an algebraic expression. Let's take each piece one by one:
[I]Difference between[/I] means we subtract:
a - b
The phrase [I]is [/I]means an equation, so we set a - b equal to 10
[B]a - b = 10[/B]
The difference between A and B is no less than 30The difference between A and B is no less than 30
The difference between means we subtract.
No less than means greater than or equal to, so we have the following inequality;
[B]A - B >= 30[/B]
the difference between A and B is no less than 30.the difference between A and B is no less than 30.
The difference between a and b:
a - b
The phrase [I]no less than[/I] means an inequality. You can also say this as [I]greater than or equal to[/I].
[B]a - b >= 30[/B]
The difference between a number and 9 is 27. Find that numberThe difference between a number and 9 is 27. Find that number
The phrase [I]a number[/I] means an arbitrary variable, let's call it x:
x
The difference between a number and 9
x - 9
The word [I]is[/I] means equal to, so we set x - 9 equal to 27:
x - 9 = 27
To solve this equation for x, we [URL='https://www.mathcelebrity.com/1unk.php?num=x-9%3D27&pl=Solve']type it in our math engine[/URL] and we get:
x = [B]36[/B]
The difference between sixty-four and yThe difference between sixty-four and y
The difference between means we subtract y from 64:
[B]64 - y[/B]
The difference between the opposite of a number and 6.The difference between the opposite of a number and 6.
The phrase [I]a number means[/I] an arbitrary variable, let's call it x.
x
The opposite of a number means we multiply by x by -1
-x
The phrase [I]the difference between[/I] means we subtract 6 from -x:
[B]-x - 6[/B]
The difference between the product of 4 and a number and the square of a numberThe difference between the product of 4 and a number and the square of a number
The phrase [I]a number[/I] means an arbitrary variable, let's call it x.
The product of 4 and a number:
4x
The square of a number means we raise x to the power of 2:
x^2
The difference between the product of 4 and a number and the square of a number:
[B]4x - x^2[/B]
The difference between the quotient of x and y, and twice zThe difference between the quotient of x and y, and twice z
The quotient of x and y means we divide x by y:
x/y
Twice z means we multiply z by 2:
2z
The difference between the quotient of x and y, and twice z means we subtract 2z from x/y
[B]x/y - 2z[/B]
The difference between the square of b and the total of b and 9The difference between the square of b and the total of b and 9
The square of b means we raise b to the power of 2:
b^2
The total of b and 9 means we add 9 to b:
b + 9
The difference means we subtract:
[B]b^2 - (b + 9)[/B]
The difference between the square of b and the total of d and gThe difference between the square of b and the total of d and g
Square of b means we raise b to the 2nd power:
b^2
Total of d and g:
d + g
The difference between the square of b and the total of d and g
[B]b^2 - (d + g)[/B]
The difference between the squares of two consecutive numbers is 141. Find the numbersThe difference between the squares of two consecutive numbers is 141. Find the numbers
Take two consecutive numbers:
n- 1 and n
Given a difference (d) between the squares of two consecutive numbers, the shortcut for this is:
2n - 1 = d
Proof of this:
n^2- (n - 1)^2 = d
n^2 - (n^2 - 2n + 1) = d
n^2 - n^2 + 2n - 1 = d
2n - 1 = d
Given d = 141, we have
2n - 1 = 141
Add 1 to each side:
2n = 142
Divide each side by 2:
2n/2 = 142/2
n = [B]71[/B]
Therefore, n - 1 = [B]70
Our two consecutive numbers are (70, 71)[/B]
Check your work
70^2 = 4900
71^2 = 5041
Difference = 5041 - 4900
Difference = 141
[MEDIA=youtube]vZJtZyYWIFQ[/MEDIA]
the difference between triple a number and double a numberthe difference between triple a number and double a number
The phrase [I]a number[/I] means an arbitrary variable, let's call it x.
Triple a number means we multiply x by 3:
3x
Double a number means we multiply x by 2:
2x
The difference means we subtract 2x from 3x:
3x - 2x
Simplifying like terms, we have:
(3 - 2)x = [B]x[/B]
The difference between two numbers is 25. The smaller number is 1/6th of the larger number. What isThe difference between two numbers is 25. The smaller number is 1/6th of the larger number. What is the value of the smaller number
Let the smaller number be s. Let the larger number be l. We're given two equations:
[LIST=1]
[*]l - s = 25
[*]s = l/6
[/LIST]
Plug in equation (2) into equation (1):
l - l/6 = 25
Multiply each side of the equation by 6 to remove the fraction:
6l - l = 150
To solve for l, we [URL='https://www.mathcelebrity.com/1unk.php?num=6l-l%3D150&pl=Solve']type this equation into our search engine[/URL] and we get:
l = 30
To solve for s, we plug in l = 30 into equation (2) above:
s = 30/6
[B]s = 5[/B]
The difference between two numbers is 96. One number is 9 times the other. What are the numbers?The difference between two numbers is 96. One number is 9 times the other. What are the numbers?
Let x be the first number
Let y be the second number
We're given two equations:
[LIST=1]
[*]x - y = 96
[*]x = 9y
[/LIST]
Substitute equation (2) into equation (1) for x
9y - y = 96
[URL='https://www.mathcelebrity.com/1unk.php?num=9y-y%3D96&pl=Solve']Plugging this equation into our math engine[/URL], we get:
y = [B]12
[/B]
If y = 12, then we plug this into equation 2:
x = 9(12)
x = [B]108[/B]
The difference between two positive numbers is 5 and the square of their sum is 169The difference between two positive numbers is 5 and the square of their sum is 169.
Let the two positive numbers be a and b. We have the following equations:
[LIST=1]
[*]a - b = 5
[*](a + b)^2 = 169
[*]Rearrange (1) by adding b to each side. We have a = b + 5
[/LIST]
Now substitute (3) into (2):
(b + 5 + b)^2 = 169
(2b + 5)^2 = 169
[URL='https://www.mathcelebrity.com/community/forums/calculator-requests.7/create-thread']Run (2b + 5)^2 through our search engine[/URL], and you get:
4b^2 + 20b + 25
Set this equal to 169 above:
4b^2 + 20b + 25 = 169
[URL='https://www.mathcelebrity.com/quadratic.php?num=4b%5E2%2B20b%2B25%3D169&pl=Solve+Quadratic+Equation&hintnum=+0']Run that quadratic equation in our search engine[/URL], and you get:
b = (-9, 4)
But the problem asks for [I]positive[/I] numbers. So [B]b = 4[/B] is one of our solutions.
Substitute b = 4 into equation (1) above, and we get:
a - [I]b[/I] = 5
[URL='https://www.mathcelebrity.com/1unk.php?num=a-4%3D5&pl=Solve']a - 4 = 5[/URL]
[B]a = 9
[/B]
Therefore, we have [B](a, b) = (9, 4)[/B]
The distance between consecutive bases is 90 feet. An outfielder catches the ball on the third baseThe distance between consecutive bases is 90 feet. An outfielder catches the ball on the third base line about 40 feet behind third base. How far would the outfielder have to throw the ball to first base?
We have a right triangle. From home base to third base is 90 feet. We add another 40 feet to the outfielder behind third base to get: 90 + 40 = 130
The distance from home to first is 90 feet.
Our hypotenuse is the distance from the outfielder to first base.
[URL='https://www.mathcelebrity.com/pythag.php?side1input=130&side2input=90&hypinput=&pl=Solve+Missing+Side']Using our Pythagorean theorem calculator[/URL], we get:
d = [B]158.11 feet[/B]
The distance between X and 8 is less than 14Distance implies the positive difference between 2 points. Therefore, we use absolute value:
|x - 8| < 14
Note, we use less than since 14 is not included.
The first significant digit in any number must be 1, 2, 3, 4, 5, 6, 7, 8, or 9. It was discovered tThe first significant digit in any number must be 1, 2, 3, 4, 5, 6, 7, 8, or 9. It was discovered that first digits do not occur with equal frequency. Probabilities of occurrence to the first digit in a number are shown in the accompanying table. The probability distribution is now known as Benford's Law. For example, the following distribution represents the first digits in 231 allegedly fraudulent checks written to a bogus company by an employee attempting to embezzle funds from his employer.
Digit, Probability
1, 0.301
2, 0.176
3, 0.125
4, 0.097
5, 0.079
6, 0.067
7, 0.058
8, 0.051
9, 0.046
[B][U]Fradulent Checks[/U][/B]
Digit, Frequency
1, 36
2, 32
3, 45
4, 20
5, 24
6, 36
7, 15
8, 16
9, 7
Complete parts (a) and (b).
(a) Using the level of significance α = 0.05, test whether the first digits in the allegedly fraudulent checks obey Benford's Law. Do the first digits obey the Benford's Law?
Yes or No
Based on the results of part (a), could one think that the employe is guilty of embezzlement?
Yes or No
Show frequency percentages
Digit Fraud Probability Benford Probability
1 0.156 0.301
2 0.139 0.176
3 0.195 0.125
4 0.087 0.097
5 0.104 0.079
6 0.156 0.067
7 0.065 0.058
8 0.069 0.051
9 0.03 0.046
Take the difference between the 2 values, divide it by the Benford's Value. Sum up the squares to get the Test Stat of 2.725281277
Critical Value Excel: =CHIINV(0.95,8) = 2.733
Since test stat is less than critical value, we cannot reject, so [B]YES[/B], it does obey Benford's Law and [B]NO[/B], there is not enough evidence to suggest the employee is guilty of embezzlement.
The IQ scores are normally distributed with a mean of 100 and a standard deviation of 15. a) What iThe IQ scores are normally distributed with a mean of 100 and a standard deviation of 15.
a) What is the probability that a randomly person has an IQ between 85 and 115?
b) Find the 90th percentile of the IQ distribution
c) If a random sample of 100 people is selected, what is the standard deviation of the sample mean?
a) [B]68%[/B] from the [URL='http://www.mathcelebrity.com/probnormdist.php?xone=50&mean=100&stdev=15&n=1&pl=Empirical+Rule']empirical rule calculator[/URL]
b) P(z) = 0.90. so z = 1.28152 using Excel NORMSINV(0.9)
(X - 100)/10 = 1.21852
X = [B]113[/B] rounded up
c) Sample standard deviation is the population standard deviation divided by the square root of the sample size
15/sqrt(100) = 15/10 =[B] 1.5[/B]
The January record high temperature in Austin, Texas is 92 degrees. The January record low temperatuThe January record high temperature in Austin, Texas is 92 degrees. The January record low temperature is -1 degree. What is the difference between the record high and low temperatures?
Difference = High - Low
Difference = 92 - -1
Difference = 92 + 1. <-- Since minus negative equals positive
Difference = [B]93 degrees[/B]
the midpoint between m and nthe midpoint between m and n
The [I]midpoint is halfway between[/I] m and n:
[B](m + n)/2[/B]
The number -2.34 can be found between which two integersThe number -2.34 can be found between which two integers
We want to take the integer of -2.34 which is -2
Since -2.34 is less than 0, we subtract 1: -2 -1 = -3
Therefore, -2.34 lies between [B]-2 and -3[/B]
-3 < -2.34 < -2
The polynomial function P(x) = 75x - 87,000 models the relationship between the number of computerThe polynomial function P(x) = 75x - 87,000 models the relationship between the number of computer briefcases x that a company sells and the profit the company makes, P(x). Find P (4000), the profit from selling 4000 computer briefcases.
Plug in 4,000 for x:
P(4000) = 75(4000) - 87,000
P(4000) = 300,000- 87,000
P(4000) = [B]213,000[/B]
The ratio between the sum of a and b and the difference of a and b is equal to 5.The ratio between the sum of a and b and the difference of a and b is equal to 5.
The sum of a and b:
a + b
The difference of a and b:
a - b
The ratio between the sum of a and b and the difference of a and b
(a + b)/(a - b)
The ratio between the sum of a and b and the difference of a and b is equal to 5.
[B](a + b)/(a - b) = 5[/B]
The set of all odd numbers between 10 and 30The set of all odd numbers between 10 and 30
[B]{11, 13, 15, 17, 19, 21, 23, 25, 27, 29}[/B]
The tempThe temperature of a solution was -23C. After adding a substance to the solution, the temperature after adding the substance to the solution was 133C.
What is the difference between the temperature of the solution before and after adding the substance
Using our [URL='https://www.mathcelebrity.com/temp-change.php?num=thetemperatureofasolutionwas-23c.afteraddingasubstancetothesolutionthetemperaturefe133c.whatisthedifferencebetweenthetemperatureofthesolutionbeforeandafteraddingthesubstance%3E&pl=Calculate+Temp+Change']temperature difference calculator[/URL], we get:
[B]156C[/B]
The temperature in Minneapolis changed from -7 fahrenheit at 6am to 7 fahrenheit at noon. What was tThe temperature in Minneapolis changed from -7 fahrenheit at 6am to 7 fahrenheit at noon. What was the difference between high and low temperatures?
Difference = High Temp - Low Temp
Difference = 7 - -7
Difference = [B]14[/B]
There are 113 identical plastic chips numbered 1 through 113 in a box. What is the probability of reThere are 113 identical plastic chips numbered 1 through 113 in a box. What is the probability of reaching into the box and randomly drawing a chip number that is greater than 44?
We want 45, 46, … 113
The formula to get inclusive number count between and including 2 numbers is:
Total numbers = L - S + 1
Total numbers = 113 - 45 + 1
Total numbers = 69
That is 69 possible numbers. We draw this out of a total of 113
[B]P(Number > 44) = 69/113
[B]P(Number > 44) [/B]= 0.610619
[MEDIA=youtube]BLBVcpdHqXU[/MEDIA][/B]
There are two numbers. The sum of 4 times the first number and 3 times the second number is 24. TheThere are two numbers. The sum of 4 times the first number and 3 times the second number is 24. The difference between 2 times the first number and 3 times the second number is 24. Find the two numbers.
Let the first number be x and the second number be y. We have 2 equations:
[LIST=1]
[*]4x + 3y = 24
[*]2x - 3y = 24
[/LIST]
Without doing anything else, we can add the 2 equations together to eliminate the y term:
(4x + 2x) + (3y - 3y) = (24 + 24)
6x = 48
Divide each side by 6:
[B]x = 8
[/B]
Substitute this into equation (1)
4(8) + 3y = 24
32 + 3y = 24
[URL='https://www.mathcelebrity.com/1unk.php?num=32%2B3y%3D24&pl=Solve']Type 32 + 3y = 24 into our search engine[/URL] and we get [B]y = 2.6667[/B].
Time ConversionsFree Time Conversions Calculator - Converts units of time between:
* nanoseconds
* microseconds
* milliseconds
* centiseconds
* kiloseconds
* seconds
* minutes
* hours
* days
* weeks
* fortnights
* months
* quarters
* years
* decades
* centurys
* milleniums
converting minutes to hours
Trig Angle conversionsFree Trig Angle conversions Calculator - Converts between degrees, radians, gradians, revolutions, and quadrants.
Trig MeasurementFree Trig Measurement Calculator - Given an angle θ, this calculates the following measurements:
Sin(θ) = Sine
Cos(θ) = Cosine
Tan(θ) = Tangent
Csc(θ) = Cosecant
Sec(θ) = Secant
Cot(θ) = Cotangent
Arcsin(x) = θ = Arcsine
Arccos(x) = θ = Arccosine
Arctan(x) =θ = Arctangent
Also converts between Degrees and Radians and Gradians
Coterminal Angles as well as determine if it is acute, obtuse, or right angle. For acute angles, a cofunction will be determined. Also shows the trigonometry function unit circle
Tristan is building a slide for his kids. The ladder is 6 feet tall and the slide is 10 feet long. WTristan is building a slide for his kids. The ladder is 6 feet tall and the slide is 10 feet long. What is the distance between the ladder and the bottom of the slide?
The answer is 8.
We have a 3-4-5 triangle. But it's scaled by 2.
3 * 2 = 6
5 * 2 = 10 (hypotenuse-slide)
4 * 2 = [B]8[/B]
True or False (a) The normal distribution curve is always symmetric to its mean. (b) If the varianceTrue or False
(a) The normal distribution curve is always symmetric to its mean.
(b) If the variance from a data set is zero, then all the observations in this data set are identical.
(c) P(A AND Ac)=1, where Ac is the complement of A.
(d) In a hypothesis testing, if the p-value is less than the significance level α, we do not have sufficient evidence to reject the null hypothesis.
(e) The volume of milk in a jug of milk is 128 oz. The value 128 is from a discrete data set.
[B](a) True, it's a bell curve symmetric about the mean
(b) True, variance measures how far a set of numbers is spread out. A variance of zero indicates that all the values are identical
(c) True. P(A) is the probability of an event and P(Ac) is the complement of the event, or any event that is not A. So either A happens or it does not. It covers all possible events in a sample space.
(d) False, we have sufficient evidence to reject H0.
(e) False. Volume can be a decimal or fractional. There are multiple values between 127 and 128. So it's continuous.[/B]
twice the difference between x and 28 is 3 times a numbertwice the difference between x and 28 is 3 times a number
The difference between x and 28:
x - 28
Twice the difference means we multiply x - 28 by 2:
2(x - 28)
The phrase [I]a number[/I] means an arbitrary variable, let's call it x
x
3 times a number:
3x
The word [I]is[/I] means equal to, so we set 2(x - 28) equal to 3x:
[B]2(x - 28) = 3x[/B]
Unit ConversionsFree Unit Conversions Calculator - Converts between a unit, pair, half-dozen, dozen, bakers dozen, and gross.
Use the definite integral to find the area between the x-axis and the function f(x)= x^2-x-12 over tUse the definite integral to find the area between the x-axis and the function f(x)= x^2-x-12 over the interval [ -5, 10].
Using our [URL='http://www.mathcelebrity.com/dfii.php?term1=x%5E2-x-12&fpt=0&ptarget1=0&ptarget2=0&itarget=-5%2C10&starget=0%2C1&nsimp=8&pl=Integral']integral calculator[/URL], we get:
[B]157.5[/B]
Van needs to enter a formula into a spreadsheet to show the outputs of an arithmetic sequence that sVan needs to enter a formula into a spreadsheet to show the outputs of an arithmetic sequence that starts with 13 and continues to add seven to each output. For now, van needs to know what the 15th output will be. Complete the steps needed to determine the 15th term in sequence.
Given a first term a1 of 13 and a change amount of 7, expand the series
The explicit formula for an [I]arithmetic series[/I] is an = a1 + (n - 1)d
d represents the common difference between each term, an - an - 1
Looking at all the terms, we see the common difference is 7, and we have a1 = 13
Therefore, our explicit formula is an = 13 + 7(n - 1)
If n = 15, then we plug it into our explicit formula above:
an = 13 + 7(n - 1)
a(15) = 15 + 7(15 - 1)
a(15) = 15 + 7 * 14
a(15) = 15 + 98
a(15) = [B]113[/B]
VectorsFree Vectors Calculator - Given 2 vectors A and B, this calculates:
* Length (magnitude) of A = ||A||
* Length (magnitude) of B = ||B||
* Sum of A and B = A + B (addition)
* Difference of A and B = A - B (subtraction)
* Dot Product of vectors A and B = A x B
A ÷ B (division)
* Distance between A and B = AB
* Angle between A and B = θ
* Unit Vector U of A.
* Determines the relationship between A and B to see if they are orthogonal (perpendicular), same direction, or parallel (includes parallel planes).
* Cauchy-Schwarz Inequality
* The orthogonal projection of A on to B, projBA and and the vector component of A orthogonal to B → A - projBA
Also calculates the horizontal component and vertical component of a 2-D vector.
Weight ConversionsFree Weight Conversions Calculator - This calculator converts between the following weight measurements:
* Ounces (oz.)
* Pounds (lb.)
* Tons
* Milligrams (mg.)
* Grams
* Kilograms (kg.)
* Centigrams (cg.)
* Micrograms (mcg.)
* Stone
What fraction lies exactly halfway between 2/3 and 3/4?What fraction lies exactly halfway between 2/3 and 3/4?
A) 3/5
B) 5/6
C) 7/12
D) 9/16
E) 17/24
Halfway means taking the average, which is dividing the sum of the fractions by 2 for 2 fractions:
1/2(2/3 + 3/4)
1/2(2/3) + 1/2(3/4)
1/3 + 3/8
We need common denominators, so [URL='https://www.mathcelebrity.com/fraction.php?frac1=1%2F3&frac2=3%2F8&pl=Add']we type this fraction sum into our search engine[/URL] and get:
[B]17/24 - Answer E[/B]
what is 828 rounded to the nearest hundredwhat is 828 rounded to the nearest hundred
828 lies between 800 and 900.
The halfway point is 850, so 828 rounds down to [B]800[/B]
What number is half between 1.24 and 1.8?What number is half between 1.24 and 1.8?
Halfway between two points is called the midpoint.
Using out [URL='http://www.mathcelebrity.com/mptnline.php?ept1=1.24&empt=&ept2=1.8&pl=Calculate+missing+Number+Line+item']midpoint calculator[/URL], we get 1.52:
Which of the following can increase power?Which of the following can increase power?
a. Increasing standard deviation
b. Decreasing standard deviation
c. Increasing both means but keeping the difference between the means constant
d. Increasing both means but making the difference between the means smaller
[B]b. Decreasing standard deviation[/B]
[LIST=1]
[*]Power increases if the standard deviation is smaller.
[*]If the difference between the means is bigger, the power is bigger.
[*]Sample size increase also increases power
[/LIST]
Which of the following involves making pairwise comparisons? a. Comparing the standard deviation ofWhich of the following involves making pairwise comparisons?
a. Comparing the standard deviation of GRE grades between two states
b. Comparing the variance of the amount of soda consumed by boys and girls in a high school
c. Comparing the mean weight between children in grades 2, 3, 4 and 5
d. Comparing the number of restaurants in New York and Boston
[B]c. Comparing the mean weight between children in grades 2, 3, 4 and 5[/B]
Pairwise comparison generally refers to any process of comparing entities in pairs to judge which of each entity is preferred, or has a greater amount of some quantitative property
Which of the followings can increase the value of t? (select all the apply) a. Increase the standarWhich of the followings can increase the value of t? (select all the apply)
a. Increase the standard deviation of difference scores
b. Decrease the standard deviation of difference scores
c. Increase the difference between means
d. Decrease the difference between means
[B]b. Decrease the standard deviation of difference scores
c. Increase the difference between means[/B]
[I]Increase numerator or decrease denominator of the t-value formula[/I]
Whitney has already baked 2 cakes, and she can bake 1 cake with each additional stick of butter sheWhitney has already baked 2 cakes, and she can bake 1 cake with each additional stick of butter she buys. Write an equation that shows the relationship between the number of additional sticks of butter s and the number of cakes c.
[LIST]
[*]Let c, the number of cakes, be represented by f(s) where s are the number of sticks of butter.
[*]We already have 2 cakes to start, and each additional stick of butter gets us one more cake.
[/LIST]
f(s) = 1s + 2
Simplify, since 1s is just s
[B]f(s) = s + 2[/B]
x is a multiple of 6 and 1 ≤ x ≤ 16x is a multiple of 6 and 1 ≤ x ≤ 16.
We want multiples of 6 between 1 and 16.
We start with 6.
Another multiple of 6 is 12
The next multiple of 6 is 18, which is out side the range of 1 ≤ x ≤ 16.
So our number set is [B]x = {6, 12}[/B]
X is not between 6 and 12X is not between 6 and 12
We want anything not between 6 and 12
[B]x < 6 U x >12[/B]
X is not between 6 and 12You can now type in to the search engine directly, X is not between 6 and 12
You are buying boxes of cookies at a bakery. Each box of cookies costs $4. In the equation below, cYou are buying boxes of cookies at a bakery. Each box of cookies costs $4. In the equation below, c represents the number of boxes of cookies you buy, and d represents the amount the cookies will cost you (in dollars). The relationship between these two variables can be expressed by the following equation: d=4c. Identify the dependent and independent variables.
[B]The variable d is dependent, and c is independent since the value of d is determined by c.[/B]
You are given a choice of taking the simple interest on $100,000 invested for 5 years at a rate of 2You are given a choice of taking the simple interest on $100,000 invested for 5 years at a rate of 2% or the interest on $100,000 invested for 5 years at an interest rate of 2% compounded daily. Which investment earns the greater amount of interest? Give the difference between the amounts of interest earned by the two investments
[URL='http://www.mathcelebrity.com/simpint.php?av=&p=100000&int=2&t=5&pl=Simple+Interest']Simple interest balance after 5 years[/URL] at 2% is $110,000.
[URL='http://www.mathcelebrity.com/compoundint.php?bal=100000&nval=1825&int=2&pl=Daily']Daily compounded interest for 5 years[/URL] at 2% is 365 days per year * 5 years = 1,825 days = [B]$110,516.79
Compound interest earns more by $110,516.79 - $110,000 = $516.79[/B]
You have $250,000 in an IRA (Individual Retirement Account) at the time you retire. You have the opYou have $250,000 in an IRA (Individual Retirement Account) at the time you retire. You have the option of investing this money in two funds: Fund A pays 5.4% annually and Fund B pays 7.9% annually. How should you divide your money between fund Fund A and Fund B to produce an annual interest income of $14,750?
You should invest $______in Fund A and $___________in Fund B.
Equation is x(.079) + (250,000 - x).054 = 14,750
.025x + 13,500 = 14,750
.025x = 1,250
[B]x = 50,000 for Fund A[/B]
So at 5.4%, we have 250,000 - 50,000 = [B]200,000[/B] for the other fund B.
You roll a standard, fair, 5-sided die and see what number you get. Find the sample space of this exYou roll a standard, fair, 5-sided die and see what number you get. Find the sample space of this experiment. Write your answer using { } symbols, and write your values in order with a comma but no spaces between
Sample Space:
[B]{1,2,3,4,5}[/B]
You split $1,500 between two savings accounts. Account A pays 5% annual interest and Account B paysYou split $1,500 between two savings accounts. Account A pays 5% annual interest and Account B pays 4% annual interest. After one year, you have earned a total of $69.50 in interest. How much money did you invest in each account. Explain.
Let a be the amount you invest in Account A. So this means you invested 1500 - A in account B. We have the following equation:
05a + (1500 - a).04 = 69.50
Simplifying, we get:
0.05a + 1560 - 0.04a = 69.50
0.01a + 60 = 69.50
Using our [URL='http://www.mathcelebrity.com/1unk.php?num=0.01a%2B60%3D69.50&pl=Solve']equation solver[/URL], we get:
[B]a = 950[/B]
So this means Account B is b = 1500 - 950 = [B]550[/B]
You went to the State Fair and spent $20. If cotton candy costs $2 and a soda pop costs $1. Which eqYou went to the State Fair and spent $20. If cotton candy costs $2 and a soda pop costs $1. Which equation represents the relation between the number of cotton candy (c) and soda pops (s) you can buy?
Our total cost for 20 at the state fair is:
Cost of Cotton Candy + Cost of Soda = 20
We know that price = cost * quantity, so we have:
2c + 1s = 20
Since 1s is written as s, we have:
[B]2c + s = 20[/B]
{x | x is an even integer between -3 and 5}{x | x is an even integer between -3 and 5}
We list even integers out in this range:
[B]{-2, 0, 2, 4}[/B]