Hilda and Ivan started running together along a cross country track. When Ivan completed the track in 25 minutes, Hilda had run only
13 of the track. Hilda’s average speed was 112 m/min slower than Ivan’s.
- How long was the cross country track in m?
- Find Hilda’s average speed in m/min.
(a)
When Ivan completed the track:
Ivan's distance = 3 u
Hilda's distance = 1 u
Extra distance covered by Ivan
= 3 u - 1 u
= 2 u
2 u = 112 x 25
2 u = 2800
1 u = 2800 ÷ 2 = 1400
Distance of the cross country track
= 3 u
= 3 x 1400
= 4200 m
(b)
Ivan's speed
= 4200 ÷ 25
= 168 m/min
Hilda's speed
= 168 - 112
= 56 m/min
Answer(s): (a) 4200 m; (b) 56 m/min