PSLE On Saturday, the number of adults to boys to girls visiting a zoo was 1 : 6 : 10. On Sunday, the number of adults visiting the zoo remained the same. However, the number of boys increased by 50% and the number of girls decreased by 40%.
- What was the ratio of the number of adults to boys to girls visiting the zoo on Sunday?
- On Saturday, 464 boys and girls visited the zoo. What was the total number of visitors at the zoo on Sunday?
|
Adults |
Boys |
Girls |
Before |
1 u |
6 u |
10 u |
Change |
|
+ 3 u |
- 4 u |
After |
1 u |
9 u |
6 u |
(a)
Increase in the number of boys
= 50% x 6 u
=
50100 x 6 u
= 3 u
Decrease in the number of girls
= 40% x 10 u
=
40100 x 10 u
= 4 u
Number of boys on Sunday
= 6 u + 3 u
= 9 u
Number of girls on Sunday
= 10 u - 4 u
= 6 u
On Sunday
Adults : Boys : Girls
1 : 9 : 6
(b)
Number of boys and girls on Saturday
= 6 u + 10 u
= 16 u
16 u = 464
1 u = 464 ÷ 16 = 29
Total number of visitors on Sunday
= 1 u + 9 u + 6 u
= 16 u
= 16 x 29
= 464
Answer(s): (a) 1 : 9 : 6; (b) 464