The distance between City L and City M was 850 km apart. A lorry travelled at an average speed of 87 km/h from City L to City M. At the same time, a van travelled at an average speed of 83 km/h from City M to City L. How much further did the lorry travel than the van when the lorry met the van on the way?
Combined speed of the lorry and the van
= 87 + 83
= 170 km/h
Time taken for the lorry and the van to meet
= 850 ÷ 170
= 5 h
Difference in the speed between the lorry and the van
= 87 - 83
= 4 km/h
Distance that the lorry travelled further than the van
= 5 x 4
= 20 km
Answer(s): 20 km