Charlie started driving from Town P towards Town Q at 13 30 at an average speed of 60 km/h. Rael began driving from Town P towards Town Q at 15 10 at an average speed of 100 km/h.
- At what time did Rael pass Charlie on the road?
- 114 hours after passing Charlie, Rael reached Town Q. At what time did Charlie reach Town Q?
(a)
From 13 30 to 15 10 = 1 h 40 min
Time that Charlie travelled before Rael started driving = 1 h 40 min
1 h = 60 min
1 h 40 min = 1
4060 h = 1
23 h
Distance that Charlie travelled before Rael started driving
= 1
23 x 60
=
53 x 60
= 100 km
Difference between Rael's and Charlie's speed
= 100 - 60
= 40 km/h
Time that Rael took to catch up with Charlie
= 100 ÷ 40
= 2.5 h
= 2 h 30 min
2 h 30 min after 15 10 = 17 40
Time that Rael passed Charlie on the road = 17 40
(b)
1
14 h = 1 h 15 min
Total time that Rael travelled
= 1 h 15 min + 2 h 30 min
= 3 h 45 min
3 h 45 min = 3
4560h = 3
34h
Distance between Town P and Town Q
= 3
34 x 100
= 375 km
Time that Charlie travelled from Town P to Town Q
= 375 ÷ 60
= 6.25 h
= 6 h 15 min
6 h 15 min after 13 30 = 19 45
Time that Charlie reached Town Q = 19 45
Answer: (a) 17 40; (b) 19 45