An observer to the right of the mirror??lens combination shown in figure sees two real images that

Question:

An observer to the right of the mirror??lens combination shown in figure sees two real images that are the same size and in the same location. One image is upright and the other is inverted. Both images are 1.50 times larger than the object. The lens has a focal length of 10.0 cm. The lens and mirror are separated by 40.0 cm. Determine the focal length of the mirror. (Don??t assume that the figure is drawn toscale.)