Esther and Ben started running together along a cross country track. When Ben completed the track in 45 minutes, Esther had run only
13 of the track. Esther’s average speed was 104 m/min slower than Ben’s.
- How long was the cross country track in m?
- Find Esther’s average speed in m/min.
(a)
When Ben completed the track:
Ben's distance = 3 u
Esther's distance = 1 u
Extra distance covered by Ben
= 3 u - 1 u
= 2 u
2 u = 104 x 45
2 u = 4680
1 u = 4680 ÷ 2 = 2340
Distance of the cross country track
= 3 u
= 3 x 2340
= 7020 m
(b)
Ben's speed
= 7020 ÷ 45
= 156 m/min
Esther's speed
= 156 - 104
= 52 m/min
Answer(s): (a) 7020 m; (b) 52 m/min