PSLE The number of girls and boys taking part in a quiz are in the ratio 1 : 8. These pupils are put into two teams. 60% of the girls and 40% of the boys are in Team F. The rest of the pupils are in Team G.
- What is the ratio of the number of pupils in Team G to Team F? Give your answer in the simplest form.
- The number of boys in Team F is more than 80. What is the smallest possible total number of pupils taking part in the quiz?
Girls |
Boys |
10 u |
80 u |
Team F |
Team G |
Team F |
Team G |
6 u |
4 u |
32 u |
48 u |
(a)
Girls : Boys
1 : 8
10 : 80
Number of girls in Team F
= 60% x 10 u
=
60100 x 10 u
= 6 u
Number of girls in Team G
= 10 u - 6 u
= 4 u
Number of boys in Team F
= 40% x 80 u
=
40100 x 80 u
= 32 u
Number of boys in Team G
= 80 u - 32 u
= 48 u
Team F : Team G
4 + 48 : 6 + 32
52 : 38
(÷2)26 : 19
(b)
Number of boys in Team F = 32 u
Since the number of boys in Team F is 32 u, it must be multiple of 32.
Number of sets of 32
= 80 ÷ 32
= 2 r 16
Since the number of boys in Team F is more than 80, the number of sets must be 1 more than 2.
1 u = 2 + 1 = 3
Smallest possible number of pupils
= 10 u + 80 u
= 90 u
= 90 x 3
= 270
Answer(s): (a) 26 : 19; (b) 270