Fanny and Seth started running together along a cross country track. When Seth completed the track in 30 minutes, Fanny had run only
37 of the track. Fanny’s average speed was 100 m/min slower than Seth’s.
- How long was the cross country track in m?
- Find Fanny’s average speed in m/min.
(a)
When Seth completed the track:
Seth's distance = 7 u
Fanny's distance = 3 u
Extra distance covered by Seth
= 7 u - 3 u
= 4 u
4 u = 100 x 30
4 u = 3000
1 u = 3000 ÷ 4 = 750
Distance of the cross country track
= 7 u
= 7 x 750
= 5250 m
(b)
Seth's speed
= 5250 ÷ 30
= 175 m/min
Fanny's speed
= 175 - 100
= 75 m/min
Answer(s): (a) 5250 m; (b) 75 m/min