The distance between City R and City S was 860 km apart. A lorry travelled at an average speed of 91 km/h from City R to City S. At the same time, a van travelled at an average speed of 81 km/h from City S to City R. 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
= 91 + 81
= 172 km/h
Time taken for the lorry and the van to meet
= 860 ÷ 172
= 5 h
Difference in the speed between the lorry and the van
= 91 - 81
= 10 km/h
Distance that the lorry travelled further than the van
= 5 x 10
= 50 km
Answer(s): 50 km