A dog, with a mass of 12.0 kg, is standing on a flatboat so that he is 25.5 m from the shore. He walks 6.0 m on the boat toward the shore and then stops. The boat has a mass of 46.0 kg. Assuming there is no friction between the boat and the water, how far is the dog from the shore now? i used [tex] x_cm = m_1 x_1 + m_2 x_2 / m_1 + m_2 [/tex] x= (12)(25.5) + (46)(6) / 12+46 and got 10.0 m Which wasn't right.. can someone please help me?