Divisibility Rules

By Gabrielle Mathew and Diana Joseph

Divisibility rules for 2, 3, 4, 6

2- The last digit of the given number should be even. That means the number should end in 0, 2, 4, 6 and 8. Ex: Is 1875494 divisible by 2? Last digit is 4 and it is even number so this fat number 1875494 is divisible by 2.

3- Add up all the digits and it should be multiple of 3 (divisible by 3). Ex: Is 2742204 divisible by 3? Add up all the digits that is 2+7+3+4+2+2+0+4=24. 24 is divisible by (8×3)/3 so this number 2742204 is divisible by 3 as well.

4- The last 2 digit (ones and tens) should be divisible by 4. Ex: Is 8763424 divisible by 4? Check the last 2 digits, that is 24 and 24 is divisible by (4×6) /3 so this big number 8763424 is divisible by 4.

6- The rule for checking whether a number is divisible by 6 is quite tricky. Since 6=2×3 We must apply the rules of 2 and 3 on a number to check if it is divisible by 6. So rules are the last digit should be even number and add up all the digits and it should be multiple of 3

Divisibility rules for 5, 9, and 10

5- The last digit should be 0 or 5. Ex: Is 498730 divisible by five? The last digit is 0 so this number 498730 is divisible by 5. Ex: Is 285 divisible by 5? The last digit is 5 so 285 is divisible by 5.


9- Add up all the digits and it should be multiple of 9 (divisible by 9). Ex: Is 2742234 divisible by 9? Add up all the digits: 2+7+3+4+2+2+3+4=27 and 27 is divisible by 9 (9×3=27) so this number 2742234 is divisible by 9.

10- The last digit should be 0 (Multiples of 10). Ex: Is 100 multiple of 10? Yes, it has a zero in the end.


Video

For me, the hardest rule is 3. Wellll, luckily, we have Gabby the host of her talk show, the Gabby show and her guest Darla to understand this concept.


Gabby and Diana
Divisibility rules