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miranda
08-25-2013, 06:24 AM
Divisibility Rules from 2 to 13



A number is divisible by:
If:


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


3
The sum of the digits is divisible by 3.


4
The number formed by the last two digits of the original number is divisible by 4.


5
The number ending in a 0 or a 5.


6
The number is divisible by both 2 and 3.


7
The last digit of the number is multiplied by 2 and subtracted from the rest of the number and the answer is either 0 or divisible by 7.


8
The last three digits form a number divisible by 8.


9
The sum of the digits is divisible by 9.


10
The last digit is 0


11
You add every second digit and then subtract all other digits and the answer is zero or a multiple of 11.


12
The number is divisible by both 3 and 4.


13
You remove the last digit from the number, then subtract 9 times the deleted digit from the remaining number. If what is left is divisible by 13, then so is the original number.



Hope these help!!;);)