Barbara and Will started running together along a cross country track. When Will completed the track in 35 minutes, Barbara had run only
49 of the track. Barbara’s average speed was 110 m/min slower than Will’s.
- How long was the cross country track in m?
- Find Barbara’s average speed in m/min.
(a)
When Will completed the track:
Will's distance = 9 u
Barbara's distance = 4 u
Extra distance covered by Will
= 9 u - 4 u
= 5 u
5 u = 110 x 35
5 u = 3850
1 u = 3850 ÷ 5 = 770
Distance of the cross country track
= 9 u
= 9 x 770
= 6930 m
(b)
Will's speed
= 6930 ÷ 35
= 198 m/min
Barbara's speed
= 198 - 110
= 88 m/min
Answer(s): (a) 6930 m; (b) 88 m/min