Question

A horizontal board weighing 227.0 N is supported at points A and B. The plank is 3.8 m in length, and points A and B are sawhorse supports a distance of D in from each end of the plank. 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.)