The photograph of a house occupies an area of 1.75 c${{m}^{2}}$ on a 35 mm slide

The photograph of a house occupies an area of 1.75 c${{m}^{2}}$ on a 35 mm slide. The slide is projected on to a screen and the area of the house on the screen is 1.55 ${{m}^{2}}$. What is the linear magnification of the projector, screen arrangement ?