GM #coffeechain

To determine if a number is divisible by 3 check if the sum of its parts are divisible by 3.

For example, 7527

7+5+2+7=21

Since 21 is divisible by 3, that means 7527 is divisible by 3, specifically 7527=3*2509

Also, this can be repeated for 9. From 7527 we found the sum of the parts is 21 which is 2+1=3 which is divisible by 3. Since we can repeat this step a second time, this means 7527 is also divisible by 9.

#math