Rachel and George started running together along a cross country track. When George completed the track in 43 minutes, Rachel had run only
37 of the track. Rachel’s average speed was 100 m/min slower than George’s.
- How long was the cross country track in m?
- Find Rachel’s average speed in m/min.
(a)
When George completed the track:
George's distance = 7 u
Rachel's distance = 3 u
Extra distance covered by George
= 7 u - 3 u
= 4 u
4 u = 100 x 43
4 u = 4300
1 u = 4300 ÷ 4 = 1075
Distance of the cross country track
= 7 u
= 7 x 1075
= 7525 m
(b)
George's speed
= 7525 ÷ 43
= 175 m/min
Rachel's speed
= 175 - 100
= 75 m/min
Answer(s): (a) 7525 m; (b) 75 m/min