City Z and City A is 468 km apart. Henry left City Z for City A at 11.00 a.m. travelling at an average speed of 78 km/h. Oliver left City Z later than Henry and caught up with him at 1.00 p.m. Oliver was travelling at a speed of 117 km/h.
- At what time did Oliver leave City Z?
- How much later did Henry arrive in City A than Oliver? 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 Henry covered when Oliver caught up with Henry
= 2 x 78
= 156 km
Time that Oliver took to travel 156 km
= 156 ÷ 117
= 1
13 h
1 h = 60 min
13 h =
13 x 60 = 20 min
1
13 h = 1 h 20 min
Time that Oliver left City Z:
1 h 20 min before 1.00 p.m. = 11.40 a.m.
(b)
Remaining distance that they had to cover to reach City A
= 468 - 156
= 312 km
Duration that Oliver had to travel before reaching City A
= 312 ÷ 117
= 2
23 h
Duration that Henry had to travel before reaching City A
= 312 ÷ 78
= 4 h
Duration that Henry took to arrive later than Oliver in City A
= 4 - 2
23= 1
13 h
Answer(s): (a) 11.40 a.m.; (b) 1
13 h