A man covered a certain distance at an average speed of 60 km/hr and comes back at the speed of 40 km/hr. Find the average speed (in km/hr) of the man during the whole journey?

58 km/hr 48 km/hr 46 km/hr 44 km/hr

48 km/hr

Let speed of man while going = A  speed of man while coming back = B  Average speed = \(\frac{2 ×A× B  }{A + B}\) = \(\frac{2 ×60 × 40  }{60 + 40}\) = \(\frac{2 × 2400  }{100}\) = 48 km/hr