Xuan and Asher started running together along a cross country track. When Asher completed the track in 21 minutes, Xuan had run only
49 of the track. Xuan’s average speed was 105 m/min slower than Asher’s.
- How long was the cross country track in m?
- Find Xuan’s average speed in m/min.
(a)
When Asher completed the track:
Asher's distance = 9 u
Xuan's distance = 4 u
Extra distance covered by Asher
= 9 u - 4 u
= 5 u
5 u = 105 x 21
5 u = 2205
1 u = 2205 ÷ 5 = 441
Distance of the cross country track
= 9 u
= 9 x 441
= 3969 m
(b)
Asher's speed
= 3969 ÷ 21
= 189 m/min
Xuan's speed
= 189 - 105
= 84 m/min
Answer(s): (a) 3969 m; (b) 84 m/min