2021 AMC 12B Problems/Problem 7
Contents
[hide]Problem
Let . What is the ratio of the sum of the odd divisors of to the sum of the even divisors of ?
Solution
Prime factorize to get . For each odd divisor of , there exist even divisors of , therefore the ratio is
Video Solution by OmegaLearn (Prime Factorization)
~ pi_is_3.14
See Also
2021 AMC 12B (Problems • Answer Key • Resources) | |
Preceded by Problem 6 |
Followed by Problem 8 |
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All AMC 12 Problems and Solutions |
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