Cathy and Olivia started off at the same spot and ran at average speeds round a 2-km circular path. Cathy took 16 minutes to complete each round. Olivia completed each round in 30 minutes.
- How far ahead of Olivia would Cathy be after 6 minute? Express your answer in metres.
- How long would it take Cathy to meet Olivia for the first time?
- How many rounds would Cathy have completed by then?
(a)
Cathy's speed =
216 =
18 km/min
Olivia's speed =
115 km/min
Difference in speeds
=
18 -
115=
15120 -
8120=
7120 km/min
Distance between Cathy and Olivia after 6 min
= 6 x
7120=
42120 km
1 km = 1000 m
42120 km =
42120 x 1000 = 350
(b)
LCM of 16 and 30 = 240
60 min = 1 h
240 min = 240 ÷ 60 = 4
Cathy and Olivia will meet for the first time after 4 h.
(c)
Rounds Cathy completed
= 240 ÷ 16
= 15
Answer(s): (a) 350 m; (b) 4 h; (c) 15