Xandra and Fred started running together along a cross country track. When Fred completed the track in 31 minutes, Xandra had run only
37 of the track. Xandra’s average speed was 112 m/min slower than Fred’s.
- How long was the cross country track in m?
- Find Xandra’s average speed in m/min.
(a)
When Fred completed the track:
Fred's distance = 7 u
Xandra's distance = 3 u
Extra distance covered by Fred
= 7 u - 3 u
= 4 u
4 u = 112 x 31
4 u = 3472
1 u = 3472 ÷ 4 = 868
Distance of the cross country track
= 7 u
= 7 x 868
= 6076 m
(b)
Fred's speed
= 6076 ÷ 31
= 196 m/min
Xandra's speed
= 196 - 112
= 84 m/min
Answer(s): (a) 6076 m; (b) 84 m/min