Roshel and Perry started running together along a cross country track. When Perry completed the track in 39 minutes, Roshel had run only
13 of the track. Roshel’s average speed was 108 m/min slower than Perry’s.
- How long was the cross country track in m?
- Find Roshel’s average speed in m/min.
(a)
When Perry completed the track:
Perry's distance = 3 u
Roshel's distance = 1 u
Extra distance covered by Perry
= 3 u - 1 u
= 2 u
2 u = 108 x 39
2 u = 4212
1 u = 4212 ÷ 2 = 2106
Distance of the cross country track
= 3 u
= 3 x 2106
= 6318 m
(b)
Perry's speed
= 6318 ÷ 39
= 162 m/min
Roshel's speed
= 162 - 108
= 54 m/min
Answer(s): (a) 6318 m; (b) 54 m/min