PSLE At a walkathon, each participant completed either a 1-km route, a 4-km route or a 5-km route.
13 of the participants completed the 1-km route,
715 of the participants completed the 4-km route and the rest completed the 5-km route. For every 1 km a participant walked, $8 was donated to charity. A total of $5760 was donated to charity.
- What is the ratio of the number of participants who completed the 1-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 walkathon?
(a)
Fraction of the participants who completed 5-km route
= 1 -
13 -
715 = 1 -
515 -
715= 1 -
1215 =
315 Ratio of participants who completed the different routes
1 km : 4 km : 5 km
5 : 7 : 3
(b)
For every 1 km a participant walked, $8 was donated to charity.
Total distance covered by the participants
= 5760 ÷ 8
= 720 km
|
1-km |
4-km |
5-km |
Total |
Number |
5 u |
7 u |
3 u |
15 u |
Value |
1 |
4 |
5 |
|
Total value |
5 u |
28 u |
15 u |
|
Total distance that the participants covered
= 1 x 5 u + 4 x 7 u + 5 x 3 u
= 5 u + 28 u + 15 u
= 48 u
48 u = 720
1 u = 720 ÷ 48 = 15
Total number of participants
= 5 u + 7 u + 3 u
= 15 u
= 15 x 15
= 225
Answer(s): (a) 5 : 7 : 3; (b) 225