Gillian and Bryan started running together along a cross country track. When Bryan completed the track in 21 minutes, Gillian had run only
49 of the track. Gillian’s average speed was 95 m/min slower than Bryan’s.
- How long was the cross country track in m?
- Find Gillian’s average speed in m/min.
(a)
When Bryan completed the track:
Bryan's distance = 9 u
Gillian's distance = 4 u
Extra distance covered by Bryan
= 9 u - 4 u
= 5 u
5 u = 95 x 21
5 u = 1995
1 u = 1995 ÷ 5 = 399
Distance of the cross country track
= 9 u
= 9 x 399
= 3591 m
(b)
Bryan's speed
= 3591 ÷ 21
= 171 m/min
Gillian's speed
= 171 - 95
= 76 m/min
Answer(s): (a) 3591 m; (b) 76 m/min