PSLE
On Monday, the number of children to men to women visiting a bird park was 7 : 4 : 5. On Tuesday, the number of children visiting the bird park remained the same. However, the number of men increased by 50% and the number of women decreased by 20%.

1. What was the ratio of the number of children to men to women visiting the bird park on Tuesday?
2. On Monday, 189 men and women visited the bird park. What was the total number of visitors at the bird park on Tuesday?

	Children	Men	Women
Before	7 u	4 u	5 u
Change		+ 2 u	- 1 u
After	7 u	6 u	4 u

(a)
Increase in the number of men
= 50% x 4 u
= ⁵⁰₁₀₀ x 4 u
= 2 u

Decrease in the number of women
= 20% x 5 u
= ²⁰₁₀₀ x 5 u
= 1 u

Number of men on Tuesday
= 4 u + 2 u
= 6 u

Number of women on Tuesday
= 5 u - 1 u
= 4 u

On Tuesday
Children : Men : Women
7 : 6 : 4

(b)
Number of men and women on Monday
= 4 u + 5 u
= 9 u

9 u = 189

1 u = 189 ÷ 9 = 21

Total number of visitors on Tuesday
= 7 u + 6 u + 4 u
= 17 u
= 17 x 21
= 357

Answer(s): (a) 7 : 6 : 4; (b) 357