2021 JMPSC Accuracy Problems/Problem 1
Contents
[hide]Problem
Find the sum of all positive multiples of that are factors of
Solution
We use the fact that and to conclude that the only multiples of that are factors of are , , and . Thus, our answer is .
~Bradygho
Solution 2
The factors of are , , and . Out of these, only , and are multiples of , so the answer is .
~Mathdreams
See also
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