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,
59 of the participants completed the 4-km route and the rest completed the 5-km route. For every 1 km a participant swam, $7 was donated to charity. A total of $6958 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 -
59 = 1 -
318 -
1018= 1 -
1318 =
518 Ratio of participants who completed the different routes
2 km : 4 km : 5 km
3 : 10 : 5
(b)
For every 1 km a participant swam, $7 was donated to charity.
Total distance covered by the participants
= 6958 ÷ 7
= 994 km
|
2-km |
4-km |
5-km |
Total |
Number |
3 u |
10 u |
5 u |
18 u |
Value |
2 |
4 |
5 |
|
Total value |
6 u |
40 u |
25 u |
|
Total distance that the participants covered
= 2 x 3 u + 4 x 10 u + 5 x 5 u
= 6 u + 40 u + 25 u
= 71 u
71 u = 994
1 u = 994 ÷ 71 = 14
Total number of participants
= 3 u + 10 u + 5 u
= 18 u
= 18 x 14
= 252
Answer(s): (a) 3 : 10 : 5; (b) 252