How much Speed must be Increase by the Car
Answer: (b) 16 km/hr
A car can finish a journey = 10 hrs
Speed of the car = 56 km/hr
therefore distance of the journey = 10 x 56 = 560 km
Other car finish a journey = 7 hr
then, the speed of the car = 560/7 = 80 km/hr.
Increased speed = 80 – 56 = 16 km/hr
Hence, the speed of the car must be increased by 16 km/hr.