PSLE At a walkathon, each participant completed either a 1-km route, a 2-km route or a 4-km route.
25 of the participants completed the 1-km route,
13 of the participants completed the 2-km route and the rest completed the 4-km route. For every 1 km a participant walked, $7 was donated to charity. A total of $4256 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 2-km route to the number who completed the 4-km route?
- What is the total number of participants at the walkathon?
(a)
Fraction of the participants who completed 4-km route
= 1 -
25 -
13 = 1 -
615 -
515= 1 -
1115 =
415 Ratio of participants who completed the different routes
1 km : 2 km : 4 km
6 : 5 : 4
(b)
For every 1 km a participant walked, $7 was donated to charity.
Total distance covered by the participants
= 4256 ÷ 7
= 608 km
|
1-km |
2-km |
4-km |
Total |
Number |
6 u |
5 u |
4 u |
15 u |
Value |
1 |
2 |
4 |
|
Total value |
6 u |
10 u |
16 u |
|
Total distance that the participants covered
= 1 x 6 u + 2 x 5 u + 4 x 4 u
= 6 u + 10 u + 16 u
= 32 u
32 u = 608
1 u = 608 ÷ 32 = 19
Total number of participants
= 6 u + 5 u + 4 u
= 15 u
= 15 x 19
= 285
Answer(s): (a) 6 : 5 : 4; (b) 285