Risa and Luke started cycling at uniform speeds from the same place in opposite direction round 900 m forest trail. Risa took 45 seconds to complete each round while Luke took 60 seconds.
- Find the distance covered per second by Risa in m.
- Find the distance covered per second by Luke in m.
- When the two cyclists next met again at the starting point, how far would Risa have covered? Express the answer in km.
(a)
Distance covered by Risa per second
= 900 ÷ 45
= 20 m
(b)
Distance covered by Luke per second
= 900 ÷ 60
= 15 m
(c)
LCM of 45 and 60 = 180
Time taken for Risa to travel and meet Luke at the starting point = 180 s
Number of rounds covered by Risa in 180 s
= 180 ÷ 45
= 4
Distance that Risa travelled to meet again
= 4 x 900
= 3600 m
1000 m = 1 km
3600 m = 3.6 km
Answer(s): (a) 20 m; (b) 15 m; (c) 3.6 km