City D and City E is 490 km apart. George left City D for City E at 8.00 a.m. travelling at an average speed of 70 km/h. Paul left City D later than George and caught up with him at 12.00 p.m. Paul was travelling at a speed of 105 km/h.
- At what time did Paul leave City D?
- How much later did George arrive in City E than Paul? Express your answer in h as a fraction or mixed number.
(a)
From 8.00 a.m. to 12.00 p.m. = 4 h
Distance that George covered when Paul caught up with George
= 4 x 70
= 280 km
Time that Paul took to travel 280 km
= 280 ÷ 105
= 2
23 h
1 h = 60 min
23 h =
23 x 60 = 40 min
2
23 h = 2 h 40 min
Time that Paul left City D:
2 h 40 min before 12.00 p.m. = 9.20 a.m.
(b)
Remaining distance that they had to cover to reach City E
= 490 - 280
= 210 km
Duration that Paul had to travel before reaching City E
= 210 ÷ 105
= 2 h
Duration that George had to travel before reaching City E
= 210 ÷ 70
= 3 h
Duration that George took to arrive later than Paul in City E
= 3 - 2
= 1 h
Answer(s): (a) 9.20 a.m.; (b) 1 h