Hazel and Esther started off at the same spot and ran at average speeds round a 4-km circular path. Hazel took 12 minutes to complete each round. Esther completed each round in 25 minutes.
- How far ahead of Esther would Hazel be after 3 minute? Express your answer in metres.
- How long would it take Hazel to meet Esther for the first time?
- How many rounds would Hazel have completed by then?
(a)
Hazel's speed =
412 =
13 km/min
Esther's speed =
425 km/min
Difference in speeds
=
13 -
425=
2575 -
1275=
1375 km/min
Distance between Hazel and Esther after 3 min
= 3 x
1375=
3975 km
1 km = 1000 m
3975 km =
3975 x 1000 = 520
(b)
LCM of 12 and 25 = 300
60 min = 1 h
300 min = 300 ÷ 60 = 5
Hazel and Esther will meet for the first time after 5 h.
(c)
Rounds Hazel completed
= 300 ÷ 12
= 25
Answer(s): (a) 520 m; (b) 5 h; (c) 25