A lorry and a Lamborghini started travelling from Town A to Town B at the same time. After 6 hours, the Lamborghini reached Town B while the lorry covered only ⁷₉ of the journey. The speed of the Lamborghini was 22 km/h more than the speed of the lorry. Find the speed of the lorry.
Extra distance covered by the Lamborghini in 6 h
= 6 x 22
= 132 km

When the Lamborghini reached Town B:
Distance covered by the Lamborghini = 9 u
Distance covered by the lorry = 7 u

Extra distance covered by the Lamborghini 
= 9 u - 7 u
= 2 u

2 u = 132

1 u = 132 ÷ 2 = 66

Distance covered by the lorry when the Lamborghini reached Town B
= 7 u
= 7 x 66
= 462 km

Speed of the lorry
= 462 ÷ 6
= 77 km/h

Answer(s): 77 km/h