Sarah and Rael started running together along a cross country track. When Rael completed the track in 48 minutes, Sarah had run only
37 of the track. Sarah’s average speed was 96 m/min slower than Rael’s.
- How long was the cross country track in m?
- Find Sarah’s average speed in m/min.
(a)
When Rael completed the track:
Rael's distance = 7 u
Sarah's distance = 3 u
Extra distance covered by Rael
= 7 u - 3 u
= 4 u
4 u = 96 x 48
4 u = 4608
1 u = 4608 ÷ 4 = 1152
Distance of the cross country track
= 7 u
= 7 x 1152
= 8064 m
(b)
Rael's speed
= 8064 ÷ 48
= 168 m/min
Sarah's speed
= 168 - 96
= 72 m/min
Answer(s): (a) 8064 m; (b) 72 m/min