Question

The ratio of boys to girls in high school is 4:7. If there were 300 more girls than boys, how many boys were in school? How many girls?

Answer 1

Explanation:

Let G and B be the number of girls and boys.

The ratio boys to girls was 4 to 7.

This means

B/G = 4/7

There were 300 more girls than boys.

This means

G = B+300

Replace in the first equation and solve for B

B/(B+300) = 4/7 ===> 7B = 4(B+300) ===> 7B = 4B + 1200 ===>

===> 7B-4B = 1200 ===> 3B = 1200 ===> B=1200/3 ===> B=400

G = B+300 ===> G = 400 + 300 ===> G=700