PSLE At a walkathon, each participant completed either a 3-km route, a 6-km route or a 7-km route.
25 of the participants completed the 3-km route,
14 of the participants completed the 6-km route and the rest completed the 7-km route. For every 1 km a participant walked, $5 was donated to charity. A total of $5665 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 6-km route to the number who completed the 7-km route?
- What is the total number of participants at the walkathon?
(a)
Fraction of the participants who completed 7-km route
= 1 -
25 -
14 = 1 -
820 -
520= 1 -
1320 =
720 Ratio of participants who completed the different routes
3 km : 6 km : 7 km
8 : 5 : 7
(b)
For every 1 km a participant walked, $5 was donated to charity.
Total distance covered by the participants
= 5665 ÷ 5
= 1133 km
|
3-km |
6-km |
7-km |
Total |
Number |
8 u |
5 u |
7 u |
20 u |
Value |
3 |
6 |
7 |
|
Total value |
24 u |
30 u |
49 u |
|
Total distance that the participants covered
= 3 x 8 u + 6 x 5 u + 7 x 7 u
= 24 u + 30 u + 49 u
= 103 u
103 u = 1133
1 u = 1133 ÷ 103 = 11
Total number of participants
= 8 u + 5 u + 7 u
= 20 u
= 20 x 11
= 220
Answer(s): (a) 8 : 5 : 7; (b) 220