Mary and Cody started running together along a cross country track. When Cody completed the track in 48 minutes, Mary had run only
58 of the track. Mary’s average speed was 96 m/min slower than Cody’s.
- How long was the cross country track in m?
- Find Mary’s average speed in m/min.
(a)
When Cody completed the track:
Cody's distance = 8 u
Mary's distance = 5 u
Extra distance covered by Cody
= 8 u - 5 u
= 3 u
3 u = 96 x 48
3 u = 4608
1 u = 4608 ÷ 3 = 1536
Distance of the cross country track
= 8 u
= 8 x 1536
= 12288 m
(b)
Cody's speed
= 12288 ÷ 48
= 256 m/min
Mary's speed
= 256 - 96
= 160 m/min
Answer(s): (a) 12288 m; (b) 160 m/min