How to find whether a number is divisible by 9 ?

How to find whether a number is divisible by 9 ?

Lets take a small example ... Is 243  divisible by 9 ?




Here is a trick 2 + 4 + 3 = 9  since 9 is divisible by 9 the number 243 is divisible by 9..



Lets take another example 281475..




So adding the numbers we get




2  +  8  + 1  +  4  + 7  +  5  =   27  as 27 is divisible by 9 the number 281475 is also divisible by 9...

Note : You can also add the result further... for e.g., the above result is 27 so 2  +  7  =  9  which is   divisible by 9