The solution simply requires the total moment about the point A. The moment generated about point A is the man's weight times the perpendicular distance from point A

With the ship at an angle of α, the perpendicular distance from point A to the line of action of the force, d, is

     d = x cosα ft

The moment is then just the distance D times the force, W, giving

     M_A = W d
           = Wx cosα   ft-lb