Question

a man on an 18 m boat is walking 2 m/s, and the boat is moving 4 m/s, how far did the boat travel in that time

Answer 1

It takes the man 9 sec to walk the length of the boat

The boat will move 4 m/s * 9 sec = 36 m distance boat travels

This assumes the boat moves at 4 m/s wrt the shore and the man walks at 2 m/s wrt the boat - this would give a total distance of

36 + 18 = 54 fm or the man or 6 m/s * 9 sec = 54 m