City D and City E is 385 km apart. Andy left City D for City E at 10.00 a.m. travelling at an average speed of 77 km/h. Dylan left City D later than Andy and caught up with him at 1.00 p.m. Dylan was travelling at a speed of 84 km/h.
- At what time did Dylan leave City D?
- How much later did Andy arrive in City E than Dylan? Express your answer in h as a fraction or mixed number.
(a)
From 10.00 a.m. to 1.00 p.m. = 3 h
Distance that Andy covered when Dylan caught up with Andy
= 3 x 77
= 231 km
Time that Dylan took to travel 231 km
= 231 ÷ 84
= 2
34 h
1 h = 60 min
34 h =
34 x 60 = 45 min
2
34 h = 2 h 45 min
Time that Dylan left City D:
2 h 45 min before 1.00 p.m. = 10.15 a.m.
(b)
Remaining distance that they had to cover to reach City E
= 385 - 231
= 154 km
Duration that Dylan had to travel before reaching City E
= 154 ÷ 84
= 1
56 h
Duration that Andy had to travel before reaching City E
= 154 ÷ 77
= 2 h
Duration that Andy took to arrive later than Dylan in City E
= 2 - 1
56=
16 h
Answer(s): (a) 10.15 a.m.; (b)
16 h