PSLE At a swimathon, each participant completed either a 3-km route, a 5-km route or a 6-km route.
15 of the participants completed the 3-km route,
815 of the participants completed the 5-km route and the rest completed the 6-km route. For every 1 km a participant swam, $8 was donated to charity. A total of $7592 was donated to charity.
- What is the ratio of the number of participants who completed the 3-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 -
15 -
815 = 1 -
315 -
815= 1 -
1115 =
415 Ratio of participants who completed the different routes
3 km : 5 km : 6 km
3 : 8 : 4
(b)
For every 1 km a participant swam, $8 was donated to charity.
Total distance covered by the participants
= 7592 ÷ 8
= 949 km
|
3-km |
5-km |
6-km |
Total |
Number |
3 u |
8 u |
4 u |
15 u |
Value |
3 |
5 |
6 |
|
Total value |
9 u |
40 u |
24 u |
|
Total distance that the participants covered
= 3 x 3 u + 5 x 8 u + 6 x 4 u
= 9 u + 40 u + 24 u
= 73 u
73 u = 949
1 u = 949 ÷ 73 = 13
Total number of participants
= 3 u + 8 u + 4 u
= 15 u
= 15 x 13
= 195
Answer(s): (a) 3 : 8 : 4; (b) 195