PSLE At a walkathon, each participant completed either a 2-km route, a 3-km route or a 5-km route.
14 of the participants completed the 2-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, $10 was donated to charity. A total of $1950 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 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 -
14 -
12 = 1 -
14 -
24= 1 -
34 =
14 Ratio of participants who completed the different routes
2 km : 3 km : 5 km
1 : 2 : 1
(b)
For every 1 km a participant walked, $10 was donated to charity.
Total distance covered by the participants
= 1950 ÷ 10
= 195 km
|
2-km |
3-km |
5-km |
Total |
Number |
1 u |
2 u |
1 u |
4 u |
Value |
2 |
3 |
5 |
|
Total value |
2 u |
6 u |
5 u |
|
Total distance that the participants covered
= 2 x 1 u + 3 x 2 u + 5 x 1 u
= 2 u + 6 u + 5 u
= 13 u
13 u = 195
1 u = 195 ÷ 13 = 15
Total number of participants
= 1 u + 2 u + 1 u
= 4 u
= 4 x 15
= 60
Answer(s): (a) 1 : 2 : 1; (b) 60