posted by Julia .
A dog, with a mass of 8.0 kg, is standing on a flatboat so that he is 26.8 m from the shore. He walks 8.6 m on the boat toward the shore and then stops. The boat has a mass of 36.0 kg. Assuming there is no friction between the boat and the water, how far is the dog from the shore now?
Use the fact that the center of mass of boat + dog stays in the same place.