We know that a number is divisible by 3 if the sum of the digits of the
number add up to a number that is divisible by 3
We know even numbers are divisible by 2
We know the last two digits determine whether or not a number is divisible
by 4
We know a number must end in 0 or 5 in order to be divisible by 5
We know a number must be even and add up to a number divisible by 3 if the
original number is to be divisible by 6
We know if a number's digits add up to a number that is divisible by 9,
then the number itself is divisble by 9
WELL BELIEVE IT OR NOT
There IS a way to see if a number is divisible by 7. Can you figure it out?