1. The problem statement, all variables and given/known data A convex lens (f1=300mm) is placed 200 mm from a concave lens (f2=-50mm). An object is placed 6m away form the convex lens. (the order is as follows: object - 6m - convex lens - 200mm - concave lens). Determine the position, magnification and nature of a final image. 2. Relevant equations for a single lens: 1/x+1/y=1/f (where x is distance from the lens to the object, y is the distance from the lens to the image), 3. The attempt at a solution Should I analyze 2 lenses separately? At first first lens, which gives the image at y1: 1/6m+1/y1=1/300mm y1=~31.5cm, so it is placed behind the second lens! Should I now consider the second lens, starting from the point, where is the image? I mean: 1/x2+1/y2=1/f2 where x2=20cm-31.5 cm=-11.5cm ? I'm a little bit confused.. And finally, how to calculate the magnification?