Kathy and David started running together along a cross country track. When David completed the track in 34 minutes, Kathy had run only
38 of the track. Kathy’s average speed was 95 m/min slower than David’s.
- How long was the cross country track in m?
- Find Kathy’s average speed in m/min.
(a)
When David completed the track:
David's distance = 8 u
Kathy's distance = 3 u
Extra distance covered by David
= 8 u - 3 u
= 5 u
5 u = 95 x 34
5 u = 3230
1 u = 3230 ÷ 5 = 646
Distance of the cross country track
= 8 u
= 8 x 646
= 5168 m
(b)
David's speed
= 5168 ÷ 34
= 152 m/min
Kathy's speed
= 152 - 95
= 57 m/min
Answer(s): (a) 5168 m; (b) 57 m/min