I am having a hard time to do this question:

Consider triangle ABC. Let D be a point on the side AB such that AD: DB = 10. Let E be a point on the segment CD such that CE: ED = 11. Let F be the point of intersection of the line L passing through AE and the side CB. Find CF: FB. (Hint: put appropriate masses at the vertices of the triangle in such a way that the point E becomes the center of masses.)

Please help me!! (Crying)