Yen and Ben started running together along a cross country track. When Ben completed the track in 25 minutes, Yen had run only
13 of the track. Yen’s average speed was 102 m/min slower than Ben’s.
- How long was the cross country track in m?
- Find Yen’s average speed in m/min.
(a)
When Ben completed the track:
Ben's distance = 3 u
Yen's distance = 1 u
Extra distance covered by Ben
= 3 u - 1 u
= 2 u
2 u = 102 x 25
2 u = 2550
1 u = 2550 ÷ 2 = 1275
Distance of the cross country track
= 3 u
= 3 x 1275
= 3825 m
(b)
Ben's speed
= 3825 ÷ 25
= 153 m/min
Yen's speed
= 153 - 102
= 51 m/min
Answer(s): (a) 3825 m; (b) 51 m/min