PSLE
On Tuesday, the number of adults to girls to boys visiting a park was 5 : 12 : 10. On Wednesday, the number of adults visiting the park remained the same. However, the number of girls decreased by 50% and the number of boys increased by 40%.

1. What was the ratio of the number of children to adults visiting the park on Wednesday?
2. On Tuesday, 748 girls and boys visited the park. What was the total number of child visitors at the park on Wednesday?

	Adults	Girls	Boys
Before	5 u	12 u	10 u
Change		- 6 u	+ 4 u
After	5 u	6 u	14 u

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

Decrease in the number of boys
= 40% x 10 u
= ⁴⁰₁₀₀ x 10 u
= 4 u

Number of girls on Wednesday
= 12 u - 6 u
= 6 u

Number of boys on Wednesday
= 10 u + 4 u
= 14 u

Number of children on Wednesday
= 6 u + 14 u
= 20 u

On Wednesday
Children : Adults
20 : 5

(b)
Number of girls and boys on Tuesday
= 12 u + 10 u
= 22 u

22 u = 748

1 u = 748 ÷ 22 = 34

Total number of child visitors on Wednesday
= 20 u
= 20 x 34
= 680

Answer(s): (a) 20 : 5; (b) 680