City W and City X is 520 km apart. John left City W for City X at 9.00 a.m. travelling at an average speed of 65 km/h. Vincent left City W later than John and caught up with him at 12.00 p.m. Vincent was travelling at a speed of 78 km/h.
- At what time did Vincent leave City W?
- How much later did John arrive in City X than Vincent? Express your answer in h as a fraction or mixed number.
(a)
From 9.00 a.m. to 12.00 p.m. = 3 h
Distance that John covered when Vincent caught up with John
= 3 x 65
= 195 km
Time that Vincent took to travel 195 km
= 195 ÷ 78
= 2
12 h
1 h = 60 min
12 h =
12 x 60 = 30 min
2
12 h = 2 h 30 min
Time that Vincent left City W:
2 h 30 min before 12.00 p.m. = 9.30 a.m.
(b)
Remaining distance that they had to cover to reach City X
= 520 - 195
= 325 km
Duration that Vincent had to travel before reaching City X
= 325 ÷ 78
= 4
16 h
Duration that John had to travel before reaching City X
= 325 ÷ 65
= 5 h
Duration that John took to arrive later than Vincent in City X
= 5 - 4
16=
56 h
Answer(s): (a) 9.30 a.m.; (b)
56 h
