A van and a Lamborghini started travelling from Town Q to Town R at the same time. After 5 hours, the Lamborghini reached Town R while the van covered only ⁵₇ of the journey. The speed of the van was 28 km/h less than the speed of the Lamborghini. Find the speed of the Lamborghini.
Extra distance covered by the Lamborghini in 5 h
= 5 x 28
= 140 km

When the Lamborghini reached Town R:
Distance covered by the Lamborghini = 7 u
Distance covered by the van = 5 u

Extra distance covered by the Lamborghini 
= 7 u - 5 u
= 2 u

2 u = 140

1 u = 140 ÷ 2 = 70

Distance covered by the Lamborghini when it reached Town R
= 7 u
= 7 x 70
= 490 km

Speed of the Lamborghini
= 490 ÷ 5
= 98 km/h

Answer(s): 98 km/h