Xuan and Albert started running together along a cross country track. When Albert completed the track in 23 minutes, Xuan had run only
13 of the track. Xuan’s average speed was 102 m/min slower than Albert’s.
- How long was the cross country track in m?
- Find Xuan’s average speed in m/min.
(a)
When Albert completed the track:
Albert's distance = 3 u
Xuan's distance = 1 u
Extra distance covered by Albert
= 3 u - 1 u
= 2 u
2 u = 102 x 23
2 u = 2346
1 u = 2346 ÷ 2 = 1173
Distance of the cross country track
= 3 u
= 3 x 1173
= 3519 m
(b)
Albert's speed
= 3519 ÷ 23
= 153 m/min
Xuan's speed
= 153 - 102
= 51 m/min
Answer(s): (a) 3519 m; (b) 51 m/min