PSLE At a walkathon, each participant completed either a 1-km route, a 3-km route or a 6-km route.
12 of the participants completed the 1-km route,
37 of the participants completed the 3-km route and the rest completed the 6-km route. For every 1 km a participant walked, $6 was donated to charity. A total of $3720 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 6-km route?
- What is the total number of participants at the walkathon?
(a)
Fraction of the participants who completed 6-km route
= 1 -
12 -
37 = 1 -
714 -
614= 1 -
1314 =
114 Ratio of participants who completed the different routes
1 km : 3 km : 6 km
7 : 6 : 1
(b)
For every 1 km a participant walked, $6 was donated to charity.
Total distance covered by the participants
= 3720 ÷ 6
= 620 km
|
1-km |
3-km |
6-km |
Total |
Number |
7 u |
6 u |
1 u |
14 u |
Value |
1 |
3 |
6 |
|
Total value |
7 u |
18 u |
6 u |
|
Total distance that the participants covered
= 1 x 7 u + 3 x 6 u + 6 x 1 u
= 7 u + 18 u + 6 u
= 31 u
31 u = 620
1 u = 620 ÷ 31 = 20
Total number of participants
= 7 u + 6 u + 1 u
= 14 u
= 14 x 20
= 280
Answer(s): (a) 7 : 6 : 1; (b) 280