Question

A geometry class has a total of 31 students. The number of males is 13 more than the number of females. How many males and how many females are in the class?

Answer 1

There are nine female students, and twenty-two male students.

Explanation:

We're told that the total number of male and female students is 31:

`m + f = 31`

We're also told that there are 13 more male than female students:

`m = f + 13`

So we can substitute the latter piece of information into the former, which will tell us how many female students there are:

`m + f = 31\\(f + 13) + f = 31\\f + f = 31 - 13\\2f = 18\\f = 9`

So there are nine female students. We can now take either of the initial tow equations, and plug the resulting f value to find m:

`m = f + 31\\m + 9 = 31\\m = 31 - 9\\m = 22`

So there are nine female students, and twenty-two male students.