You are at the store and the price of your goods costs 100. You have two coupons that you can use $30 off the price of your goods or 15% off the price of your goods. Which is better?

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You are at the store and the price of your goods costs 100

You have two coupons that you can use:

• $30 off the price of your goods
• 15 percent off the price of your goods

Which coupon yields the better value?

Calculate Dollar off Price denoted as Pd:

Pd = Price - Dollar off

Pd = $100.00 - $30.00

Pd = $70.00

Calculate Percentage off Price denoted as Pp:

Discount Percentage = 0.15

Calculate Price Paid:

If the discount is x%, that means you pay for (1 - x)%

Pp = Price x (1 - Discount Percentage)

Pp = 100 x (1 - 0.15)

Pp = 100 x (0.85)

Pp = $85.00

Comparison Results:

In this case, the dollar discount of 30 is better than 15% off

Use the dollar coupon

Project the price where the percentage discount beats the dollar discount:

In other words, we need to know when 15% x Price ≥ 30

From above, 15% = 0.15

Divide each side of the equation by 0.15

Cancelling 0.15 from the left side of the equation to solve for price, we get: