Find the odd number less than 100 that is divisible by 9, and when divided by 10 has a remainder of | MathCelebrity Forum

Find the odd number less than 100 that is divisible by 9, and when divided by 10 has a remainder of

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Find the odd number less than 100 that is divisible by 9, and when divided by 10 has a remainder of 7.

From our divisibility calculator, we see a number is divisible by 9 if the sum of its digits is divisible by 9.

Starting from 1 to 99, we find all numbers with a digit sum of 9.

This would be digits with 0 and 9, 1 and 8, 2 and 7, 3 and 6, and 4 and 5.
9
18
27
36
45
54
63
72
81
90

Now remove even numbers since the problem asks for odd numbers
9
27
45
63
81

Now, divide each number by 10, and find the remainder
9/10 = 0
27/10 = 2 R 7

We stop here. 27 is an odd number, less than 100, with a remainder of 7 when divided by 10.
 
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