The distance between two towns is covered in 7 hours at a speed of 50 km/h. By how much should the speed (in km/h) be increased so that 2 hours of travelling time will be saved?
Answer & explanation
Correct answer: option 2
Distance = Speed × Time
Distance = 50 × 7 = 350 km
To cover distance in 2 hour less . i.e. 5 hours
Speed = \(\frac{350}{5}\) = 70 km/h
Increment in speed = 70 - 50 = 20 km/h