Divisibility Rules for division by: 2,3,4,5,6,7,8,9,10 and 12
1. numbers are divisible by 2 if
the last digit ends in an even number
example: 358 (8 ÷ 2=4) so 358 is divisible by 2.
2. numbers are divisible by 3 if
adding the digits of a number results in a number divisible by 3
example: 456 (4+5+6 = 15) 15÷3 = 5, 456 is divisible by 3.
3. numbers are divisible by 4 if
the number formed by the last two digits are evenly divisible by 4
example: 288 (88÷4 = 22) eighty-eight is divisible by 4.
4. numbers are divisible by 5 if
the number ends in 0 or 5
example: 3,450 ends in 0 so 3,450 is divisible by 5.
5. numbers are divisible by 6 if
the number is divisible by 2 and 3
(use the rules for divisibility by 2 and 3)
example: 78 (78 ends in 8 so it is divisible by 2);
(7 + 8 =15, so 78 is divisible by 3) so 78 is divisible by 6.
6. numbers are divisible by 7 if
take the last digit in a number
double, and subtract the last digit in your number from the
rest of the digits
repeat the process for larger numbers
example: 357 (double the 7 to get 14. Subtract 14 from 35 to
get 21 which is divisible by 7)
7. numbers are divisible by 8 if
the last three digits are divisible by 8, so is the entire
number.
example: 6,032 (the last three digits are divisible by 8) so the
entire number is also divisible by 8.
8. numbers are divisible by 9 if
the sum of the digits are divisible by 9.
example: 2,826 (2+8+2+6 = 18) so 2,826 is divisible by 9.
9. numbers are divisible by 10 if
the number ends in 0 (in ones place)
example: 6,540 (6,540÷ 10 = 654) so 6,540 is divisible by 10.
10. numbers are divisible by 12 if
divisible by 3 and 4.
(use the rules for divisibility by 3 and 4)
example: 8,256 (8+2+5+6 = 21, 21 is divisible by 3);(8,256,
56 is divisible by 4) so 8,256 is divisible by 12.
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