PSLE At a walkathon, each participant completed either a 1-km route, a 3-km route or a 5-km route.
15 of the participants completed the 1-km route,
12 of the participants completed the 3-km route and the rest completed the 5-km route. For every 1 km a participant walked, $7 was donated to charity. A total of $4032 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 3-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 -
15 -
12 = 1 -
210 -
510= 1 -
710 =
310 Ratio of participants who completed the different routes
1 km : 3 km : 5 km
2 : 5 : 3
(b)
For every 1 km a participant walked, $7 was donated to charity.
Total distance covered by the participants
= 4032 ÷ 7
= 576 km
|
1-km |
3-km |
5-km |
Total |
Number |
2 u |
5 u |
3 u |
10 u |
Value |
1 |
3 |
5 |
|
Total value |
2 u |
15 u |
15 u |
|
Total distance that the participants covered
= 1 x 2 u + 3 x 5 u + 5 x 3 u
= 2 u + 15 u + 15 u
= 32 u
32 u = 576
1 u = 576 ÷ 32 = 18
Total number of participants
= 2 u + 5 u + 3 u
= 10 u
= 10 x 18
= 180
Answer(s): (a) 2 : 5 : 3; (b) 180