The distance between City U and City V was 990 km apart. A lorry travelled at an average speed of 84 km/h from City U to City V. At the same time, a bus travelled at an average speed of 81 km/h from City V to City U. 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
= 84 + 81
= 165 km/h
Time taken for the lorry and the bus to meet
= 990 ÷ 165
= 6 h
Difference in the speed between the lorry and the bus
= 84 - 81
= 3 km/h
Distance that the lorry travelled further than the bus
= 6 x 3
= 18 km
Answer(s): 18 km