Question

If the ratio of boys to girls at the school is 2:5, and there are 40 boys, how many girls are there?

Answer 1

There are 100 girls in the school

Explanation:

Let the total number of people be x

To find the number of girls in the class we must first find the total number of people in the class

First find the total parts

That's

2 + 5 = 7

2/7 of the total number of people are boys

So we have

2/7 × x = 40

Multiply through by 7

2x = 280

Divide both sides by 2

x = 140

There are 140 people in the school

Finding the number of girls we have

5/7 × 140

= 100

There are 100 girls in the school

Hope this helps you