PSLE On Friday, the number of adults to girls to boys visiting a theme park was 5 : 10 : 2. On Saturday, the number of adults visiting the theme park remained the same. However, the number of girls increased by 20% and the number of boys decreased by 50%.
- What was the ratio of the number of adults to girls to boys visiting the theme park on Saturday?
- On Friday, 552 girls and boys visited the theme park. What was the total number of visitors at the theme park on Saturday?
|
Adults |
Girls |
Boys |
Before |
5 u |
10 u |
2 u |
Change |
|
+ 2 u |
- 1 u |
After |
5 u |
12 u |
1 u |
(a)
Increase in the number of girls
= 20% x 10 u
=
20100 x 10 u
= 2 u
Decrease in the number of boys
= 50% x 2 u
=
50100 x 2 u
= 1 u
Number of girls on Saturday
= 10 u + 2 u
= 12 u
Number of boys on Saturday
= 2 u - 1 u
= 1 u
On Saturday
Adults : Girls : Boys
5 : 12 : 1
(b)
Number of girls and boys on Friday
= 10 u + 2 u
= 12 u
12 u = 552
1 u = 552 ÷ 12 = 46
Total number of visitors on Saturday
= 5 u + 12 u + 1 u
= 18 u
= 18 x 46
= 828
Answer(s): (a) 5 : 12 : 1; (b) 828