PSLE At a walkathon, each participant completed either a 3-km route, a 5-km route or a 6-km route.
15 of the participants completed the 3-km route,
13 of the participants completed the 5-km route and the rest completed the 6-km route. For every 1 km a participant walked, $5 was donated to charity. A total of $4180 was donated to charity.
- What is the ratio of the number of participants who completed the 3-km route to the number who completed the 5-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 -
15 -
13 = 1 -
315 -
515= 1 -
815 =
715 Ratio of participants who completed the different routes
3 km : 5 km : 6 km
3 : 5 : 7
(b)
For every 1 km a participant walked, $5 was donated to charity.
Total distance covered by the participants
= 4180 ÷ 5
= 836 km
|
3-km |
5-km |
6-km |
Total |
Number |
3 u |
5 u |
7 u |
15 u |
Value |
3 |
5 |
6 |
|
Total value |
9 u |
25 u |
42 u |
|
Total distance that the participants covered
= 3 x 3 u + 5 x 5 u + 6 x 7 u
= 9 u + 25 u + 42 u
= 76 u
76 u = 836
1 u = 836 ÷ 76 = 11
Total number of participants
= 3 u + 5 u + 7 u
= 15 u
= 15 x 11
= 165
Answer(s): (a) 3 : 5 : 7; (b) 165