PSLE At a walkathon, each participant completed either a 3-km route, a 4-km route or a 7-km route.
12 of the participants completed the 3-km route,
718 of the participants completed the 4-km route and the rest completed the 7-km route. For every 1 km a participant walked, $6 was donated to charity. A total of $6624 was donated to charity.
- What is the ratio of the number of participants who completed the 3-km route to the number who completed the 4-km route to the number who completed the 7-km route?
- What is the total number of participants at the walkathon?
(a)
Fraction of the participants who completed 7-km route
= 1 -
12 -
718 = 1 -
918 -
718= 1 -
1618 =
218 Ratio of participants who completed the different routes
3 km : 4 km : 7 km
9 : 7 : 2
(b)
For every 1 km a participant walked, $6 was donated to charity.
Total distance covered by the participants
= 6624 ÷ 6
= 1104 km
|
3-km |
4-km |
7-km |
Total |
Number |
9 u |
7 u |
2 u |
18 u |
Value |
3 |
4 |
7 |
|
Total value |
27 u |
28 u |
14 u |
|
Total distance that the participants covered
= 3 x 9 u + 4 x 7 u + 7 x 2 u
= 27 u + 28 u + 14 u
= 69 u
69 u = 1104
1 u = 1104 ÷ 69 = 16
Total number of participants
= 9 u + 7 u + 2 u
= 18 u
= 18 x 16
= 288
Answer(s): (a) 9 : 7 : 2; (b) 288