City M and City N is 315 km apart. Sam left City M for City N at 10.00 a.m. travelling at an average speed of 63 km/h. Bryan left City M later than Sam and caught up with him at 12.00 p.m. Bryan was travelling at a speed of 108 km/h.
- At what time did Bryan leave City M?
- How much later did Sam arrive in City N than Bryan? Express your answer in h as a fraction or mixed number.
(a)
From 10.00 a.m. to 12.00 p.m. = 2 h
Distance that Sam covered when Bryan caught up with Sam
= 2 x 63
= 126 km
Time that Bryan took to travel 126 km
= 126 ÷ 108
= 1
16 h
1 h = 60 min
16 h =
16 x 60 = 10 min
1
16 h = 1 h 10 min
Time that Bryan left City M:
1 h 10 min before 12.00 p.m. = 10.50 a.m.
(b)
Remaining distance that they had to cover to reach City N
= 315 - 126
= 189 km
Duration that Bryan had to travel before reaching City N
= 189 ÷ 108
= 1
34 h
Duration that Sam had to travel before reaching City N
= 189 ÷ 63
= 3 h
Duration that Sam took to arrive later than Bryan in City N
= 3 - 1
34= 1
14 h
Answer(s): (a) 10.50 a.m.; (b) 1
14 h
