Question

The ratio of girls to boys in the junior high band is 5 to 7. At the beginning of the year, there were 72 students in the band. By the end of the year, the ratio of girls to boys was 3 to 4. If there are now 48 boys in the band, how many girls joined the band during the school year?

Answer 1

Ratio is 5girls:7boys with total 72 students 
5+7= 12
72➗12= 6
6(5:7)= 30 girls : 42 boys

New ratio is 3:4 with 48 boys

48➗4= 12

So for girls 3x12= 36

So started with 30 girls ended with 36 girls... 6 girls joined band during the school year.

Answer 2

36 is the amount of girls and 48 boys