Esther and Seth started running together along a cross country track. When Seth completed the track in 25 minutes, Esther had run only
38 of the track. Esther’s average speed was 115 m/min slower than Seth’s.
- How long was the cross country track in m?
- Find Esther’s average speed in m/min.
(a)
When Seth completed the track:
Seth's distance = 8 u
Esther's distance = 3 u
Extra distance covered by Seth
= 8 u - 3 u
= 5 u
5 u = 115 x 25
5 u = 2875
1 u = 2875 ÷ 5 = 575
Distance of the cross country track
= 8 u
= 8 x 575
= 4600 m
(b)
Seth's speed
= 4600 ÷ 25
= 184 m/min
Esther's speed
= 184 - 115
= 69 m/min
Answer(s): (a) 4600 m; (b) 69 m/min