A car driver travels from the plains to the hill station, which are 200 km apart at an average speed of 50km/hr. in return trip, he covers the same distance at an average speed of 20km/hr. the average speed of the car over the entire distance of 400 km is
Pick one.
A) 8.95km/hr
B) 26.7km/hr
C) 27.8km/hr
D) 28.5km/hr
E) 8.45km/hr
average speed = (2*50*20)/50+20 km/hr   =28.5 km/hr   Answer (28.5km/hr)
<result>D</result>
A car driver travels from the plains to the hill station, which are 200 km apart at an average speed of 50km/hr. in return trip, he covers the same distance at an average speed of 20km/hr. the average speed of the car over the entire distance of 400 km is