PSLE At a swimathon, each participant completed either a 2-km route, a 4-km route or a 5-km route.
16 of the participants completed the 2-km route,
23 of the participants completed the 4-km route and the rest completed the 5-km route. For every 1 km a participant swam, $10 was donated to charity. A total of $4370 was donated to charity.
- What is the ratio of the number of participants who completed the 2-km route to the number who completed the 4-km route to the number who completed the 5-km route?
- What is the total number of participants at the swimathon?
(a)
Fraction of the participants who completed 5-km route
= 1 -
16 -
23 = 1 -
16 -
46= 1 -
56 =
16 Ratio of participants who completed the different routes
2 km : 4 km : 5 km
1 : 4 : 1
(b)
For every 1 km a participant swam, $10 was donated to charity.
Total distance covered by the participants
= 4370 ÷ 10
= 437 km
|
2-km |
4-km |
5-km |
Total |
Number |
1 u |
4 u |
1 u |
6 u |
Value |
2 |
4 |
5 |
|
Total value |
2 u |
16 u |
5 u |
|
Total distance that the participants covered
= 2 x 1 u + 4 x 4 u + 5 x 1 u
= 2 u + 16 u + 5 u
= 23 u
23 u = 437
1 u = 437 ÷ 23 = 19
Total number of participants
= 1 u + 4 u + 1 u
= 6 u
= 6 x 19
= 114
Answer(s): (a) 1 : 4 : 1; (b) 114