Distance covered by the car = 80 × 9 = 720 km
\ Speed = 720⁄6 = 120 km/hr
\ Speed gain = 120 – 80 = 40 km/hr
A car finishes a journey in nine hours at the speed of 80 km/hr. If the same distance is to be covered in six hours how much more speed does the car have to gain?
[1] 8 km/hr
[2] 40 km/hr
[3] 12 km/hr
[4] 16 km/hr
[5] None of these