The distance between City M and City N was 810 km apart. A convertible travelled at an average speed of 90 km/h from City M to City N. At the same time, a lorry travelled at an average speed of 72 km/h from City N to City M. How much further did the convertible travel than the lorry when the convertible met the lorry on the way?
Combined speed of the convertible and the lorry
= 90 + 72
= 162 km/h
Time taken for the convertible and the lorry to meet
= 810 ÷ 162
= 5 h
Difference in the speed between the convertible and the lorry
= 90 - 72
= 18 km/h
Distance that the convertible travelled further than the lorry
= 5 x 18
= 90 km
Answer(s): 90 km