A bus covers a certain distance travelling at a speed of 40 km/h and returns to the starting point at a speed of 60 km/h. The average speed (in km/h) for the entire journey is:
Answer & explanation
Correct answer: option 1
Average speed = \(\frac{2 × S1 × S2 }{S1 + S2 }\)
= \(\frac{2 × 60 × 40 }{60 + 40 }\)
= \(\frac{4800 }{100 }\)
= 48 km/h