PSLE At a walkathon, each participant completed either a 1-km route, a 3-km route or a 5-km route.
16 of the participants completed the 1-km route,
13 of the participants completed the 3-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 $3520 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 -
16 -
13 = 1 -
16 -
26= 1 -
36 =
36 Ratio of participants who completed the different routes
1 km : 3 km : 5 km
1 : 2 : 3
(b)
For every 1 km a participant walked, $8 was donated to charity.
Total distance covered by the participants
= 3520 ÷ 8
= 440 km
|
1-km |
3-km |
5-km |
Total |
Number |
1 u |
2 u |
3 u |
6 u |
Value |
1 |
3 |
5 |
|
Total value |
1 u |
6 u |
15 u |
|
Total distance that the participants covered
= 1 x 1 u + 3 x 2 u + 5 x 3 u
= 1 u + 6 u + 15 u
= 22 u
22 u = 440
1 u = 440 ÷ 22 = 20
Total number of participants
= 1 u + 2 u + 3 u
= 6 u
= 6 x 20
= 120
Answer(s): (a) 1 : 2 : 3; (b) 120