City L and City M were 429 km apart. A van travelled from City L towards City M. At the same time, a bus started from City M to City L. After travelling 1
15 h, the two vehicles were still 195 km apart. If the ratio of the average speed of the bus to that of the van was 6 : 7, find
- the average speed of the bus.
- the time taken for them to meet travelling the rest of the journey. Express your answer in h.
(a)
Distance covered in 1
15 h by the two vehicles
= 429 - 195
= 234 km
Combined speed of the two vehicles
= 234 ÷
65 = 234 x
56 = 195 km/h
Average speed of the bus : Average speed of the van = 6 : 7
6 u + 7 u = 13 u
13 u = 195
1 u = 195 ÷ 13 = 15
Average speed of the bus
= 6 u
= 6 x 15
= 90 km/h
(b)
Time taken for the bus and the van to meet travelling the rest of the journey
= 195 ÷ 195
= 1 h
Answer(s): (a) 90 km/h; (b) 1 h