PSLE
The number of girls and boys taking part in a contest are in the ratio 1 : 6. These students are put into two teams. 40% of the girls and 30% of the boys are in Team F. The rest of the students are in Team G.

1. What is the ratio of the number of students in Team G to Team F? Give your answer in the simplest form.
2. The number of boys in Team F is more than 40. What is the smallest possible total number of students taking part in the contest?

Girls		Boys
10 u		60 u
Team F	Team G	Team F	Team G
4 u	6 u	18 u	42 u

(a)
Girls : Boys
1 : 6
10 : 60

Number of girls in Team F
= 40% x 10 u
= ⁴⁰₁₀₀ x 10 u
= 4 u

Number of girls in Team G
= 10 u - 4 u
= 6 u

Number of boys in Team F
= 30% x 60 u
= ³⁰₁₀₀ x 60 u
= 18 u

Number of boys in Team G
= 60 u - 18 u
= 42 u

Team F : Team G
6 + 42 : 4 + 18 
48 : 22 _(÷2)
24 : 11

(b)
Number of boys in Team F = 18 u

Since the number of boys in Team F is 18 u, it must be multiple of 18.

Number of sets of 18
= 40 ÷ 18
= 2 r 4

Since the number of boys in Team F is more than 40, the number of sets must be 1 more than 2.

1 u = 2 + 1 = 3

Smallest possible number of students
= 10 u + 60 u
= 70 u
= 70 x 3
= 210

Answer(s): (a) 24 : 11; (b) 210