A number is a multiple of 3 if you can add up the digits and the sum is also a multiple of 3. But why does it work that way? And do similar phenomena appear in other base number systems?

Question

A number is a multiple of 3 if you can add up the digits and the sum is also a multiple of 3. But why does it work that way? And do similar phenomena appear in other base number systems?

In: 17

Answer 1

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