Two questions:(adsbygoogle = window.adsbygoogle || []).push({});

1. We add the digits of any number. If the sum is divisible by 3, then that number is divisible by 3. Why?

2. Does this work for a number of more than 2 digits?

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# Why if the sum of a number's digits is divisible by 3, that no. is divisible by 3?

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