As shown in the figure, a combination of a thin plano concave lens and a thin plano convex lens is used to image an object placed at infinity. The…

As shown in the figure, a combination of a thin plano concave lens and a thin plano convex lens is used to image an object placed at infinity. The radius of curvature of both the lenses is $\displaystyle 30$ cm and refraction index of the material for both the lenses is $\displaystyle 1.75$ . Both the lenses are placed at distance of $\displaystyle 40$ cm from each other. Due to the combination, the image of the object is formed at distance $\displaystyle x=$ $\displaystyle \_\_\_\_$ cm, from concave lens.