1. The problem statement, all variables and given/known data A dog weighing 10.8 lb, is standing on a flatboat so that he is 21.4 ft from shore. He walks 8.5 ft on the boat toward shore and then halts. The boat weighs 46.4 lb, and one can assume there is no friction between it and the water. How far is he from shore at the end of this time? (Hint: The center of mass of the boat + dog does not move. Why?) 2. Relevant equations 3. The attempt at a solution Initially I considered that the boat will move exactly as much as the dog does, but I'm no longer sure it will. I am now of the opinion that maybe the dog will move a proportional distance of 8.50 ft x (his weight/total weight) But I am not sure and would like a second opinion. Thanks in advance.