Sabrina and Bobby started running together along a cross country track. When Bobby completed the track in 48 minutes, Sabrina had run only
37 of the track. Sabrina’s average speed was 112 m/min slower than Bobby’s.
- How long was the cross country track in m?
- Find Sabrina’s average speed in m/min.
(a)
When Bobby completed the track:
Bobby's distance = 7 u
Sabrina's distance = 3 u
Extra distance covered by Bobby
= 7 u - 3 u
= 4 u
4 u = 112 x 48
4 u = 5376
1 u = 5376 ÷ 4 = 1344
Distance of the cross country track
= 7 u
= 7 x 1344
= 9408 m
(b)
Bobby's speed
= 9408 ÷ 48
= 196 m/min
Sabrina's speed
= 196 - 112
= 84 m/min
Answer(s): (a) 9408 m; (b) 84 m/min