A man goes uphill with an average speed of 35 km/hr, and covers down with an average speed of 45 km/hr. The distance travelled in both the cases being the same , the average speed for the entire journey is?
Correct Answer: 39 3/8 km/hr.
Explanation:
Average speed = 2uv / (u + v)
= ( 2 x 35 x 45) / (35 + 45) km/hr.
= 39 3/8 km/hr
