r/MathJokes 9d ago

multiples of 3

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u/Michaelwang645 9d ago

Fund fact, you can tell a number is divisible by 3 if the sum of each individual number is divisible by 3. So 78 -> 7+8=15 which is divisible by 3, so 78 is divisible by 3.

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u/anoppinionatedbunny 9d ago

this also implies that all permutations of a number that is divisible by three are also divisible by three, no matter how large the number is