A boy A having a weight of 80 lb and girl B having a weight of 65

Question:

A boy A having a weight of 80 lb and girl B having a weight of 65 lb stand motionless at the ends of the toboggan, which has a weigh of 20 lb. if A walks to B and stops, and both walk back together to the original position of A, determine the final position of the toboggan just after the motion stops. Neglect friction

4 ft