Anna and Jaslyn started off at the same spot and ran at average speeds round a 2-km circular path. Anna took 24 minutes to complete each round. Jaslyn completed each round in 30 minutes.
- How far ahead of Jaslyn would Anna be after 3 minute? Express your answer in metres.
- How long would it take Anna to meet Jaslyn for the first time?
- How many rounds would Anna have completed by then?
(a)
Anna's speed =
224 =
112 km/min
Jaslyn's speed =
115 km/min
Difference in speeds
=
112 -
115=
560 -
460=
160 km/min
Distance between Anna and Jaslyn after 3 min
= 3 x
160=
360 km
1 km = 1000 m
360 km =
360 x 1000 = 50
(b)
LCM of 24 and 30 = 120
60 min = 1 h
120 min = 120 ÷ 60 = 2
Anna and Jaslyn will meet for the first time after 2 h.
(c)
Rounds Anna completed
= 120 ÷ 24
= 5
Answer(s): (a) 50 m; (b) 2 h; (c) 5