A car is running at a speed of 64 km/h to cover a certain distance in 40 min. At what speed should the car run into reduce the time of the journey to 30 min ?

85.33 km/h 74.65 km/h 54 km/h 84.78 km/h

85.33 km/h

Distance = Speed × Time = 64 × \(\frac{40  }{60 }\) = 42.667 km To cover the distance in 30 min , Speed  = \(\frac{Distance }{Time}\) = \(\frac{42.667 }{30}\) × 60 = 85.33 km/h