PSLE At a walkathon, each participant completed either a 1-km route, a 3-km route or a 4-km route.
13 of the participants completed the 1-km route,
512 of the participants completed the 3-km route and the rest completed the 4-km route. For every 1 km a participant walked, $10 was donated to charity. A total of $4960 was donated to charity.
- What is the ratio of the number of participants who completed the 1-km route to the number who completed the 3-km route to the number who completed the 4-km route?
- What is the total number of participants at the walkathon?
(a)
Fraction of the participants who completed 4-km route
= 1 -
13 -
512 = 1 -
412 -
512= 1 -
912 =
312 Ratio of participants who completed the different routes
1 km : 3 km : 4 km
4 : 5 : 3
(b)
For every 1 km a participant walked, $10 was donated to charity.
Total distance covered by the participants
= 4960 ÷ 10
= 496 km
|
1-km |
3-km |
4-km |
Total |
Number |
4 u |
5 u |
3 u |
12 u |
Value |
1 |
3 |
4 |
|
Total value |
4 u |
15 u |
12 u |
|
Total distance that the participants covered
= 1 x 4 u + 3 x 5 u + 4 x 3 u
= 4 u + 15 u + 12 u
= 31 u
31 u = 496
1 u = 496 ÷ 31 = 16
Total number of participants
= 4 u + 5 u + 3 u
= 12 u
= 12 x 16
= 192
Answer(s): (a) 4 : 5 : 3; (b) 192