PSLE At a swimathon, each participant completed either a 2-km route, a 4-km route or a 5-km route.
12 of the participants completed the 2-km route,
613 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 $14220 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 -
12 -
613 = 1 -
1326 -
1226= 1 -
2526 =
126 Ratio of participants who completed the different routes
2 km : 4 km : 5 km
13 : 12 : 1
(b)
For every 1 km a participant swam, $10 was donated to charity.
Total distance covered by the participants
= 14220 ÷ 10
= 1422 km
|
2-km |
4-km |
5-km |
Total |
Number |
13 u |
12 u |
1 u |
26 u |
Value |
2 |
4 |
5 |
|
Total value |
26 u |
48 u |
5 u |
|
Total distance that the participants covered
= 2 x 13 u + 4 x 12 u + 5 x 1 u
= 26 u + 48 u + 5 u
= 79 u
79 u = 1422
1 u = 1422 ÷ 79 = 18
Total number of participants
= 13 u + 12 u + 1 u
= 26 u
= 26 x 18
= 468
Answer(s): (a) 13 : 12 : 1; (b) 468