PSLE
On Wednesday, the number of children to men to women visiting a park was 7 : 5 : 5. On Thursday, the number of children visiting the park remained the same. However, the number of men decreased by 20% and the number of women increased by 40%.

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

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

(a)
Increase in the number of men
= 20% x 5 u
= ²⁰₁₀₀ x 5 u
= 1 u

Decrease in the number of women
= 40% x 5 u
= ⁴⁰₁₀₀ x 5 u
= 2 u

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

Number of women on Thursday
= 5 u + 2 u
= 7 u

Number of adults on Thursday
= 4 u + 7 u
= 11 u

On Thursday
Adults : Children
11 : 7

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

10 u = 480

1 u = 480 ÷ 10 = 48

Total number of adult visitors on Thursday
= 11 u
= 11 x 48
= 528

Answer(s): (a) 11 : 7; (b) 528