There were 140 children enrolled in the Fiona Cooking School in 2023. ³₇ of the children were girls. Additional children joined the cooking school in 2024. For every 3 girls who joined the cooking school, 2 boys joined the cooking school. If there was an equal number of boys and girls in 2024, how many boys joined the school in that year?

	Girls	Boys
Before	60	80
Change	+ 3 u	+ 2 u
After	60 + 3 u	80 + 2 u

Fraction of children who are boys
= 1 - ³₇
= ⁴₇

Number of girls at first
= ³₇ x 140
= 60

Number of boys at first
= ⁴₇ x 140
= 80

Girls who joined : Boys who joined
3 : 2

The number of boys and girls in the end is the same.

60 + 3 u = 80 + 2 u
3 u - 2 u = 80 - 60

1 u = 20

Number of boys who joined the school in that year
= 2 u
= 2 x 20
= 40

Answer(s): 40