City P and City Q is 300 km apart. Lee left City P for City Q at 8.00 a.m. travelling at an average speed of 60 km/h. Harry left City P later than Lee and caught up with him at 11.00 a.m. Harry was travelling at a speed of 108 km/h.
- At what time did Harry leave City P?
- How much later did Lee arrive in City Q than Harry? Express your answer in h as a fraction or mixed number.
(a)
From 8.00 a.m. to 11.00 a.m. = 3 h
Distance that Lee covered when Harry caught up with Lee
= 3 x 60
= 180 km
Time that Harry took to travel 180 km
= 180 ÷ 108
= 1
23 h
1 h = 60 min
23 h =
23 x 60 = 40 min
1
23 h = 1 h 40 min
Time that Harry left City P:
1 h 40 min before 11.00 a.m. = 9.20 a.m.
(b)
Remaining distance that they had to cover to reach City Q
= 300 - 180
= 120 km
Duration that Harry had to travel before reaching City Q
= 120 ÷ 108
= 1
19 h
Duration that Lee had to travel before reaching City Q
= 120 ÷ 60
= 2 h
Duration that Lee took to arrive later than Harry in City Q
= 2 - 1
19=
89 h
Answer(s): (a) 9.20 a.m.; (b)
89 h