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A number is
divisible by:

If:

Example:

2

The last digit is even (0,2,4,6,8)

128 is
129 is not

3

The sum of the digits is divisible by 3

381 (3+8+1=12, and 12÷3 = 4) Yes

217 (2+1+7=10, and 10÷3 = 3 ¹/₃) No

4

The last 2 digits are divisible by 4

1312 is (12÷4=3)
7019 is not

5

The last digit is 0 or 5

175 is
809 is not

6

The number is divisible by both 2 and 3

114 (it is even, and 1+1+4=6 and 6÷3 = 2) Yes

308 (it is even, but 3+

0+8=11 and 11÷3 = 3 ²/₃) No

9

The sum of the digits is divisible by 9

(Note: you can apply this rule to that answer again if you want)

1629 (1+6+2+9=18, and again, 1+8=9) Yes

2013 (2+0+1+3=6) No

10

The number ends in 0

220 is
221 is not

12

The number is divisible by both 3 and 4

648 (6+4+8=18 and 18÷3=6, also 48÷4=12) Yes

916 (9+1+6=16, 16÷3= 5 ¹/₃) No