PSLE At a swimathon, each participant completed either a 2-km route, a 5-km route or a 6-km route.
13 of the participants completed the 2-km route,
29 of the participants completed the 5-km route and the rest completed the 6-km route. For every 1 km a participant swam, $5 was donated to charity. A total of $2200 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 5-km route to the number who completed the 6-km route?
- What is the total number of participants at the swimathon?
(a)
Fraction of the participants who completed 6-km route
= 1 -
13 -
29 = 1 -
39 -
29= 1 -
59 =
49 Ratio of participants who completed the different routes
2 km : 5 km : 6 km
3 : 2 : 4
(b)
For every 1 km a participant swam, $5 was donated to charity.
Total distance covered by the participants
= 2200 ÷ 5
= 440 km
|
2-km |
5-km |
6-km |
Total |
Number |
3 u |
2 u |
4 u |
9 u |
Value |
2 |
5 |
6 |
|
Total value |
6 u |
10 u |
24 u |
|
Total distance that the participants covered
= 2 x 3 u + 5 x 2 u + 6 x 4 u
= 6 u + 10 u + 24 u
= 40 u
40 u = 440
1 u = 440 ÷ 40 = 11
Total number of participants
= 3 u + 2 u + 4 u
= 9 u
= 9 x 11
= 99
Answer(s): (a) 3 : 2 : 4; (b) 99