A bus and a Lamborghini started travelling from Town B to Town C at the same time. After 2 hours, the Lamborghini reached Town C while the bus covered only ⁷₁₀ of the journey. The speed of the bus was 30 km/h less than the speed of the Lamborghini. Find the speed of the Lamborghini.
Extra distance covered by the Lamborghini in 2 h
= 2 x 30
= 60 km

When the Lamborghini reached Town C:
Distance covered by the Lamborghini = 10 u
Distance covered by the bus = 7 u

Extra distance covered by the Lamborghini 
= 10 u - 7 u
= 3 u

3 u = 60

1 u = 60 ÷ 3 = 20

Distance covered by the Lamborghini when it reached Town C
= 10 u
= 10 x 20
= 200 km

Speed of the Lamborghini
= 200 ÷ 2
= 100 km/h

Answer(s): 100 km/h