City S and City T is 390 km apart. Vaidev left City S for City T at 7.00 a.m. travelling at an average speed of 65 km/h. Julian left City S later than Vaidev and caught up with him at 10.00 a.m. Julian was travelling at a speed of 78 km/h.
- At what time did Julian leave City S?
- How much later did Vaidev arrive in City T than Julian? Express your answer in h as a fraction or mixed number.
(a)
From 7.00 a.m. to 10.00 a.m. = 3 h
Distance that Vaidev covered when Julian caught up with Vaidev
= 3 x 65
= 195 km
Time that Julian 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 Julian left City S:
2 h 30 min before 10.00 a.m. = 7.30 a.m.
(b)
Remaining distance that they had to cover to reach City T
= 390 - 195
= 195 km
Duration that Julian had to travel before reaching City T
= 195 ÷ 78
= 2
12 h
Duration that Vaidev had to travel before reaching City T
= 195 ÷ 65
= 3 h
Duration that Vaidev took to arrive later than Julian in City T
= 3 - 2
12=
12 h
Answer(s): (a) 7.30 a.m.; (b)
12 h
