City E and City F is 560 km apart. Bobby left City E for City F at 9.00 a.m. travelling at an average speed of 70 km/h. Tim left City E later than Bobby and caught up with him at 1.00 p.m. Tim was travelling at a speed of 112 km/h.
- At what time did Tim leave City E?
- How much later did Bobby arrive in City F than Tim? Express your answer in h as a fraction or mixed number.
(a)
From 9.00 a.m. to 1.00 p.m. = 4 h
Distance that Bobby covered when Tim caught up with Bobby
= 4 x 70
= 280 km
Time that Tim took to travel 280 km
= 280 ÷ 112
= 2
12 h
1 h = 60 min
12 h =
12 x 60 = 30 min
2
12 h = 2 h 30 min
Time that Tim left City E:
2 h 30 min before 1.00 p.m. = 10.30 a.m.
(b)
Remaining distance that they had to cover to reach City F
= 560 - 280
= 280 km
Duration that Tim had to travel before reaching City F
= 280 ÷ 112
= 2
12 h
Duration that Bobby had to travel before reaching City F
= 280 ÷ 70
= 4 h
Duration that Bobby took to arrive later than Tim in City F
= 4 - 2
12= 1
12 h
Answer(s): (a) 10.30 a.m.; (b) 1
12 h
