1. The problem statement, all variables and given/known data First: My course has sig figs disabled. We are recording all that is shown in calculations. Its my instructor's choice, not mine. Please do not lecture on sig figs. I know already. ;) Problem: A person stands in a stationary canoe and throws a 4.85-kg stone with a velocity of +7.73 m/s at an angle of 35.3 ° above the horizontal. The person and canoe have a combined mass of 102 kg. Ignore air resistance and effects of the water and find the horizontal recoil velocity (magnitude and direction) of the person and canoe. 3. The attempt at a solution horizontal velocity = velocity of 7.73m/s * cos 35.3 = 6.3087 mass of stone 4.58kg * horizontal velocity of 6.3087 = 28.894 kg m/s 28.894 kg m/s = 102kg * recoil velocity 28.894 / 102 = recoil velocity = -0.28327 m/s This is incorrect. What have I done wrong? The negative is for the opposite direction movement.