Elyse and Billy started running together along a cross country track. When Billy completed the track in 37 minutes, Elyse had run only
35 of the track. Elyse’s average speed was 98 m/min slower than Billy’s.
- How long was the cross country track in m?
- Find Elyse’s average speed in m/min.
(a)
When Billy completed the track:
Billy's distance = 5 u
Elyse's distance = 3 u
Extra distance covered by Billy
= 5 u - 3 u
= 2 u
2 u = 98 x 37
2 u = 3626
1 u = 3626 ÷ 2 = 1813
Distance of the cross country track
= 5 u
= 5 x 1813
= 9065 m
(b)
Billy's speed
= 9065 ÷ 37
= 245 m/min
Elyse's speed
= 245 - 98
= 147 m/min
Answer(s): (a) 9065 m; (b) 147 m/min