Mathnasium #MathTricks: Divisibility (Rule for 9s)

Jan 5, 2022

A number is divisible by 9 if the sum of the digits is divisible by 9.

To determine if the number 738 is divisible by 9, we find the sum of its digits. Seven plus three plus eight gives us a final sum of eighteen. Eighteen is divisible by 9. So,

738 is divisible by 9.

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