PSLE
In a school, 70% of the members in Reading Club and 80% of the members in Drama Club are girls. Both clubs have the same number of boys. The Reading Club has 35 less girls than the Drama Club. How many members are there in Drama Club?

	Reading Club		Drama Club
Types	Girls	Boys	Girls	Boys
Comparing the girls and the boys in each club	7x1	3x1	4x3	1x3
Comparing the boys in 2 clubs		1		1
	7 u	3 u	12 u	3 u

70% = ⁷⁰₁₀₀ = ⁷₁₀

Fraction of the members in Reading Club that are boys
= 1 - ⁷₁₀
= ³₁₀

80% = ⁸⁰₁₀₀ = ⁴₅

Fraction of the members in Drama club that are boys
= 1 - ⁴₅
= ¹₅

The number of boys in both clubs is the same. Make the numerators the same. LCM of 3 and 1 is 3. 

3x110x1 of the members in Reading Club = 1x35x3 of the members in Drama Club
310of the members in Reading Club = 315 of the members in Drama Club

Number of less girls in Reading Club than Drama Club
= 12 u - 7 u
= 5 u

5 u = 35

1 u = 35 ÷ 5 = 7

Number of members in Drama Club
= 15 u
= 15 x 7
= 105

Answer(s): 105