A man goes to a place in the car at speed of 160 km/h and comes back at a lower speed. If the average speed is 64 km/h in total, then the return speed (in km/h) is:

40

We know ,

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

According to question ,

64 = \(\frac{2 × 160 × S2 }{160 + S2}\)

160 + S2 = \(\frac{2 × 160 × S2 }{64}\)

4 × S2 = 160 km

S2 = 40 km/h

So , Speed while returning back is 40 km/h