Answer:
The answer is 40
Step-by-step explanation:
28/x=7/10
firs you need to setup this equation and solve it to get 40
there are 12 girls in the band and 28 boys in the band and I know this because 12+28=40 just like 3/10 + 7/10= 10/10
12 divided by 4 is 3
28 divided by 4 is 7