City Z and City A is 240 km apart. Ian left City Z for City A at 7.00 a.m. travelling at an average speed of 60 km/h. Valen left City Z later than Ian and caught up with him at 9.00 a.m. Valen was travelling at a speed of 80 km/h.
- At what time did Valen leave City Z?
- How much later did Ian arrive in City A than Valen? Express your answer in h as a fraction or mixed number.
(a)
From 7.00 a.m. to 9.00 a.m. = 2 h
Distance that Ian covered when Valen caught up with Ian
= 2 x 60
= 120 km
Time that Valen 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 Valen left City Z:
1 h 30 min before 9.00 a.m. = 7.30 a.m.
(b)
Remaining distance that they had to cover to reach City A
= 240 - 120
= 120 km
Duration that Valen had to travel before reaching City A
= 120 ÷ 80
= 1
12 h
Duration that Ian had to travel before reaching City A
= 120 ÷ 60
= 2 h
Duration that Ian took to arrive later than Valen in City A
= 2 - 1
12=
12 h
Answer(s): (a) 7.30 a.m.; (b)
12 h
