Question

There were an equal number of boys and girls in a school auditorium. After 24 boys left the auditorium, there were 3 times as many girls as boys. How many children were there in the beginning?

Answer 1

Explanation:

x=# of boys, y=# of girls

after 24 boys have left, we have 3 times as many girls

y=3(x-24)

because there are the same number of girls as boys - we create this equation

x=y

then we can use substitution

y=3(y-24)

y=3y-72

-2y=-72

y=36

because there are 36 boys, that means there are also 36 girls - leaving you with 72 children in the beginning.

hope this helps!!