City N and City P is 420 km apart. Andy left City N for City P at 11.00 a.m. travelling at an average speed of 60 km/h. Howard left City N later than Andy and caught up with him at 1.00 p.m. Howard was travelling at a speed of 80 km/h.
- At what time did Howard leave City N?
- How much later did Andy arrive in City P than Howard? Express your answer in h as a fraction or mixed number.
(a)
From 11.00 a.m. to 1.00 p.m. = 2 h
Distance that Andy covered when Howard caught up with Andy
= 2 x 60
= 120 km
Time that Howard took to travel 120 km
= 120 ÷ 80
= 1
12 h
1 h = 60 min
12 h =
12 x 60 = 30 min
1
12 h = 1 h 30 min
Time that Howard left City N:
1 h 30 min before 1.00 p.m. = 11.30 a.m.
(b)
Remaining distance that they had to cover to reach City P
= 420 - 120
= 300 km
Duration that Howard had to travel before reaching City P
= 300 ÷ 80
= 3
34 h
Duration that Andy had to travel before reaching City P
= 300 ÷ 60
= 5 h
Duration that Andy took to arrive later than Howard in City P
= 5 - 3
34= 1
14 h
Answer(s): (a) 11.30 a.m.; (b) 1
14 h
