Answer: 252 Boys, 168 Girls
Explanation:
420 would be 100% of the school students.
If you wanna find the number of girls, you need to divide 420/100 in order to get 1% and then multiply it by 40.
So then you would get
420/100 x 40 = 168
Then in order to get the boys just subtract 168 from 420
420- 168= 252