Question

10.
A car travels the first half of a distance between two places at a speed of 30 km/hr and the
second half of the distance at 50 km/hr. The average speed of the car for the whole journey is
(A) 42.5 km/hr
(B) 40.0 km/hr
(C) 37.5 km/hr
(D) 35.0 km/hr​

Answer 1

1. let total distance be x
2. travel=x/2 with speed speed of 30km/hour

again

travel X/2 with speed of 50km/h

total distance=X km total time = 2hours

average speed=total distance/total time = 40km/hours