What is the upward force exerted on the board by the support?

A long uniform board weighs 66.1 N (13.2 lbs) rests on a support at its mid point. Two children weighing 491.0 N (98.2 lbs) and 371.0 N (74.2 lbs) stand on the board so that the board is balanced. What is the upward force exerted on the board by the support?
1 answer 1