WHAT IS THE DIVISIBILITY RULE OF 7 ?!?!?!?!?

Hi!
There are two rules to check the divisibility of 7.
 
Rule 1:
(i)  Take the last digit in a number.
(ii)  Double and subtract the last digit in your number from the rest of the digits.
(iii)  Repeat the process for larger numbers.
 
Example: To check the divisibility of 357, double the 7 to get 14. Subtract 14 from 35 to get 21 which is divisible by 7 and hence it can be said that 357 is divisible by 7.
 
Rule 2:
(i)  Take the number and multiply each digit beginning on the right hand side (ones) by 1, 3, 2, 6, 4, 5. Repeat this sequence as
  necessary
(ii)  Add the products.
(iii)  If the sum is divisible by 7 - so is your number.
 
Example: To check the divisibility 2016 by 7, we proceed in the following manner
6(1) + 1(3) + 0(2) + 2(6) = 21
21 is divisible by 7 and hence it can be said that 2016 is also divisible by 7.
 
Hope! This will help you.
Cheers!!!

  • 19

 its better to manually divide and check than remembering a rule..its useless

  • 1
What are you looking for?