The distance between City R and City S was 840 km apart. A lorry travelled at an average speed of 85 km/h from City R to City S. At the same time, a bus travelled at an average speed of 83 km/h from City S to City R. How much further did the lorry travel than the bus when the lorry met the bus on the way?
Combined speed of the lorry and the bus
= 85 + 83
= 168 km/h
Time taken for the lorry and the bus to meet
= 840 ÷ 168
= 5 h
Difference in the speed between the lorry and the bus
= 85 - 83
= 2 km/h
Distance that the lorry travelled further than the bus
= 5 x 2
= 10 km
Answer(s): 10 km