A man walks 7.5 km at a speed of 3 km/h. At what speed would the man need two walk during the next 2 h to have an average of 4 km/h for the entire session?
Correct Answer: 5.25 km/h
Explanation:
Let speed of walking be V km/h.
Total time taken = (7.5/3) + 2 = 4.5 h
Total distance covered = (7.5 + 2V) km
∴ (7.5 + 2V)/4.5 = 4
⇒ 7.5 + 2V = 18
⇒ 2V = 10.5
⇒ V = 5.25
∴ Speed of walking = 5.25 km/h
