Xandra and Zeph started running together along a cross country track. When Zeph completed the track in 50 minutes, Xandra had run only
13 of the track. Xandra’s average speed was 112 m/min slower than Zeph’s.
- How long was the cross country track in m?
- Find Xandra’s average speed in m/min.
(a)
When Zeph completed the track:
Zeph's distance = 3 u
Xandra's distance = 1 u
Extra distance covered by Zeph
= 3 u - 1 u
= 2 u
2 u = 112 x 50
2 u = 5600
1 u = 5600 ÷ 2 = 2800
Distance of the cross country track
= 3 u
= 3 x 2800
= 8400 m
(b)
Zeph's speed
= 8400 ÷ 50
= 168 m/min
Xandra's speed
= 168 - 112
= 56 m/min
Answer(s): (a) 8400 m; (b) 56 m/min