A horizontal board weighing 227.0 N is supported at points A and B in the figure below. The plank serves as a platform for a painter, who weighs 553.0 N. Find the maximum distance D, such that the plank will not tip, no matter where the painter stands. (Let L = 3.80 m.)

Answer 1

There is not "figure beloiw". Try setting the total of moments equal to zero. The weight of the board acts through the center of mass.