divisibility


we can find out quickly if a larger number is divisible by a smaller number by using some shortcuts

 

 

some common divisibility tests

 

2 ——- if the last digit is even or 0

3 ——- if the sum of all the digits is divisible by 3

4 ——-if the last 2 digits form a number that is divisible by 4

5 ——- if the last digit is 5 or 0

6 ——- if the number is divisible by both 2 and 3

9 ——–if the sum of all the digits is divisible by 9

10 ——if the last digit is 0

11 ——if the difference is 11 or 0 [ add digits 1st,3rd,5th….; also add digits 2nd,4th,6th….; find the                difference between the numbers ]

12 ——if the number is divisible by both 3 and 4

18 ——if the number is divisible by both 2 and 9

etc

 

 

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