City T and City U is 385 km apart. Ethan left City T for City U at 8.00 a.m. travelling at an average speed of 77 km/h. John left City T later than Ethan and caught up with him at 10.00 a.m. John was travelling at a speed of 84 km/h.
- At what time did John leave City T?
- How much later did Ethan arrive in City U than John? Express your answer in h as a fraction or mixed number.
(a)
From 8.00 a.m. to 10.00 a.m. = 2 h
Distance that Ethan covered when John caught up with Ethan
= 2 x 77
= 154 km
Time that John took to travel 154 km
= 154 ÷ 84
= 1
56 h
1 h = 60 min
56 h =
56 x 60 = 50 min
1
56 h = 1 h 50 min
Time that John left City T:
1 h 50 min before 10.00 a.m. = 8.10 a.m.
(b)
Remaining distance that they had to cover to reach City U
= 385 - 154
= 231 km
Duration that John had to travel before reaching City U
= 231 ÷ 84
= 2
34 h
Duration that Ethan had to travel before reaching City U
= 231 ÷ 77
= 3 h
Duration that Ethan took to arrive later than John in City U
= 3 - 2
34=
14 h
Answer(s): (a) 8.10 a.m.; (b)
14 h