Question

John has 30 friends. Then amount of male friends is 4 more than the number of female friends. Which system can be used to find the number of male and female friends?

Answer 1

The required system of equations is:

`m+f = 30\\m = f+4`

Explanation:

First of all, the variables have to be selected to represent the quantities.

Let m be the number of male friends and let f be the number of female friends.

Then according to first statement "John has 30 friends"

`m+f = 30\ \ \ \ Eqn\ 1`

And according to second statement "amount of male friends is 4 more than the number of female friends."

`m = f+4\ \ \ \ Eqn\ 2`

Hence the required system of equations is:

`m+f = 30\\m = f+4`