A man covers 1/3 part of a distance at the speed of 40 km/hr. He covers the remaining distance at the speed of 50 km/hr. What is the average speed (in km/hr) for this journey?
Show answer & explanation
Correct answer: A
Explanation
Let total distance = 150 km
First part = 50 km
Second part = 100 km
Total time = 50/40 + 100/50
= 5/4 + 2
= 13/4 hours
Average speed = 150 / (13/4)
= 600/13 km/h