Glen started driving from City D towards City E at 14 30 at an average speed of 60 km/h. Japheth began driving from City D towards City E at 16 10 at an average speed of 100 km/h.
- At what time did Japheth pass Glen on the road?
- 114 hours after passing Glen, Japheth reached City E. At what time did Glen reach City E?
(a)
From 14 30 to 16 10 = 1 h 40 min
Time that Glen travelled before Japheth started driving = 1 h 40 min
1 h = 60 min
1 h 40 min = 1
4060 h = 1
23 h
Distance that Glen travelled before Japheth started driving
= 1
23 x 60
=
53 x 60
= 100 km
Difference between Japheth's and Glen's speed
= 100 - 60
= 40 km/h
Time that Japheth took to catch up with Glen
= 100 ÷ 40
= 2.5 h
= 2 h 30 min
2 h 30 min after 16 10 = 18 40
Time that Japheth passed Glen on the road = 18 40
(b)
1
14 h = 1 h 15 min
Total time that Japheth travelled
= 1 h 15 min + 2 h 30 min
= 3 h 45 min
3 h 45 min = 3
4560h = 3
34h
Distance between City D and City E
= 3
34 x 100
= 375 km
Time that Glen travelled from City D to City E
= 375 ÷ 60
= 6.25 h
= 6 h 15 min
6 h 15 min after 14 30 = 20 45
Time that Glen reached City E = 20 45
Answer: (a) 18 40; (b) 20 45