Question:
A and B are two cities. A man travels from A to B at 35 km/ hr and returns at the rate of 15 km/hr. Find his average speed for the whole journey?
A20 km/hr
B21 km/hr
C22.5 km/hr
D22 km/hr
Answer:
B. 21 km/hr
Explanation:
2xy/(x+y) = (2 x 35 x 15) / (35+15) = (2 x 35 x 15) / 50 = 21 km/hr