There were 132 children enrolled in the Xandra Cooking School in 2023. ⁵₁₁ of the children were boys. Additional children joined the cooking school in 2024. For every 5 boys who joined the cooking school, 4 girls joined the cooking school. If there was an equal number of girls and boys in 2024, how many girls joined the school in that year?

	Boys	Girls
Before	60	72
Change	+ 5 u	+ 4 u
After	60 + 5 u	72 + 4 u

Fraction of children who are girls
= 1 - ⁵₁₁
= ⁶₁₁

Number of boys at first
= ⁵₁₁ x 132
= 60

Number of girls at first
= ⁶₁₁ x 132
= 72

Boys who joined : Girls who joined
5 : 4

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

60 + 5 u = 72 + 4 u
5 u - 4 u = 72 - 60

1 u = 12

Number of girls who joined the school in that year
= 4 u
= 4 x 12
= 48

Answer(s): 48