PSLE
In a school, 60% of the members in Reading Club and 75% of the members in Drama Club are girls. Both clubs have the same number of boys. The Drama Club has 33 more girls than the Reading Club. How many girls are there altogether?

	Reading Club		Drama Club
Types	Girls	Boys	Girls	Boys
Comparing the girls and the boys in each club	3x1	2x1	3x2	1x2
Comparing the boys in 2 clubs		1		1
	3 u	2 u	6 u	2 u

60% = ⁶⁰₁₀₀ = ³₅

Fraction of the members in Reading Club that are boys
= 1 - ³₅
= ²₅

75% = ⁷⁵₁₀₀ = ³₄

Fraction of the members in Drama club that are boys
= 1 - ³₄
= ¹₄

The number of boys in both clubs is the same. Make the numerators the same. LCM of 2 and 1 is 2. 

2x15x1 of the members in Reading Club = 1x24x2 of the members in Drama Club
25of the members in Reading Club = 28 of the members in Drama Club

Number of more girls in Drama Club than Reading Club
= 6 u - 3 u
= 3 u

3 u = 33

1 u = 33 ÷ 3 = 11

Total number of girls
= 3 u + 6 u
= 9 u
= 9 x 11
= 99

Answer(s): 99