Lucy and Tom started running together along a cross country track. When Tom completed the track in 48 minutes, Lucy had run only
47 of the track. Lucy’s average speed was 111 m/min slower than Tom’s.
- How long was the cross country track in m?
- Find Lucy’s average speed in m/min.
(a)
When Tom completed the track:
Tom's distance = 7 u
Lucy's distance = 4 u
Extra distance covered by Tom
= 7 u - 4 u
= 3 u
3 u = 111 x 48
3 u = 5328
1 u = 5328 ÷ 3 = 1776
Distance of the cross country track
= 7 u
= 7 x 1776
= 12432 m
(b)
Tom's speed
= 12432 ÷ 48
= 259 m/min
Lucy's speed
= 259 - 111
= 148 m/min
Answer(s): (a) 12432 m; (b) 148 m/min