Jane and George started running together along a cross country track. When George completed the track in 21 minutes, Jane had run only
49 of the track. Jane’s average speed was 110 m/min slower than George’s.
- How long was the cross country track in m?
- Find Jane’s average speed in m/min.
(a)
When George completed the track:
George's distance = 9 u
Jane's distance = 4 u
Extra distance covered by George
= 9 u - 4 u
= 5 u
5 u = 110 x 21
5 u = 2310
1 u = 2310 ÷ 5 = 462
Distance of the cross country track
= 9 u
= 9 x 462
= 4158 m
(b)
George's speed
= 4158 ÷ 21
= 198 m/min
Jane's speed
= 198 - 110
= 88 m/min
Answer(s): (a) 4158 m; (b) 88 m/min