Answer:
Yes , it is possible .
Explanation:
Suppose they travelled from A to B , a distance of 800 m at a velocity of
40m /s and then come back on the same path covering a distance of 200 m at the rate of 20/ s .In other words their velocity in their return journey was -20m /s .
Net displacement = 600 m
Total time taken = (800 / 40) + (200 / 20)
= 20 + 10 = 30 s
Average velocity = net displacement / total time
= 600 / 30 = 20 m /s .
Hence average velocity of 20 m /s is possible .
