PSLE
On Thursday, the number of children to men to women visiting a zoo was 7 : 5 : 10. On Friday, the number of children visiting the zoo remained the same. However, the number of men increased by 40% and the number of women decreased by 50%.

1. What was the ratio of the number of children to men to women visiting the zoo on Friday?
2. On Thursday, 480 men and women visited the zoo. What was the total number of visitors at the zoo on Friday?

	Children	Men	Women
Before	7 u	5 u	10 u
Change		+ 2 u	- 5 u
After	7 u	7 u	5 u

(a)
Increase in the number of men
= 40% x 5 u
= ⁴⁰₁₀₀ x 5 u
= 2 u

Decrease in the number of women
= 50% x 10 u
= ⁵⁰₁₀₀ x 10 u
= 5 u

Number of men on Friday
= 5 u + 2 u
= 7 u

Number of women on Friday
= 10 u - 5 u
= 5 u

On Friday
Children : Men : Women
7 : 7 : 5

(b)
Number of men and women on Thursday
= 5 u + 10 u
= 15 u

15 u = 480

1 u = 480 ÷ 15 = 32

Total number of visitors on Friday
= 7 u + 7 u + 5 u
= 19 u
= 19 x 32
= 608

Answer(s): (a) 7 : 7 : 5; (b) 608