DIVISIBILITY TEST FOR 12, 20 and 25

 DIVISIBILITY TESTS FOR 20 AND 25 COMMON KEY - NUMBER FORMED BY LAST TWO DIGITS

 DIVISIBILITY TEST FOR 20

 In a given number ,if the number formed by last two digits is among {00,20,40,60,80} then the given number is divisible by 20. Number formed by last two digits {00,20,40,60,80} 

example 32400, 678920, 9980..

DIVISIBILITY TEST FOR 25 

In a given number ,if the number formed by last two digits is among {00,25,50,75} then the given number is divisible by 25. 

example 324525, 6767550...

DIVISIBILITY TEST FOR 12

 If a given number is divisible by 3 and 4, then the given number is divisible by 12.

Divisible by 3- sum of the digits divisible by 3 

Divisible by 4- no formed by last two digits divisible by 4.

3348, 99936

Exercise :

1.Find out 5 number which is divisible by both 20 and 25

2. Find out 5 number which is divisible by 12