A truck goes from Haryana to Bangalore with an average speed of 60 km/h. The journey takes 30 hours. It returns from Bangalore to Haryana on the same road with an average speed of 40 km/h. What was the average speed of the truck during the roundtrip?

48 km/h

Average speed = \(\frac{2 × S1 × S2 }{S1 + S2}\)

= \(\frac{2 × 60 × 40 }{60 + 40}\)

= \(\frac{4800 }{100}\)

=   48 km/h