PSLE
On Wednesday, the number of children to women to men visiting a bird park was 3 : 12 : 5. On Thursday, the number of children visiting the bird park remained the same. However, the number of women increased by 50% and the number of men decreased by 20%.

1. What was the ratio of the number of children to women to men visiting the bird park on Thursday?
2. On Wednesday, 850 women and men visited the bird park. What was the total number of visitors at the bird park on Thursday?

	Children	Women	Men
Before	3 u	12 u	5 u
Change		+ 6 u	- 1 u
After	3 u	18 u	4 u

(a)
Increase in the number of women
= 50% x 12 u
= ⁵⁰₁₀₀ x 12 u
= 6 u

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

Number of women on Thursday
= 12 u + 6 u
= 18 u

Number of men on Thursday
= 5 u - 1 u
= 4 u

On Thursday
Children : Women : Men
3 : 18 : 4

(b)
Number of women and men on Wednesday
= 12 u + 5 u
= 17 u

17 u = 850

1 u = 850 ÷ 17 = 50

Total number of visitors on Thursday
= 3 u + 18 u + 4 u
= 25 u
= 25 x 50
= 1250

Answer(s): (a) 3 : 18 : 4; (b) 1250