How can I know the answer to an equation like this? when we use modulus operator 25%7

Answer 1

Modulo operator is used to return the remainder of division operation, in your case 25 % 7 means you will get whatever value there is (if any) from 25 divided by 7, since 25 cannot be fully divisible by 7 there will be a remainder which is 4.

Hth, cmiiw

Answer 2

Modulo operator is used when you want to use the remainder of an integer division. In 25%7 , the quotient will be 3 and remainder will be 4. Use the modulo operator when the problem needs.