An object is placed at a distance of 75 cm from a screen. Where should a convex lens of focal length 12 cm be placed so as to obtain a real image of the object?

Explanation

To solve the problem of where to place a convex lens of focal length 12 cm to obtain a real image on a screen that is 75 cm away, we can follow these steps:

### Step 1: Define the Variables
- Let the distance from the lens to the object be \( x \) cm.
- Therefore, the distance from the lens to the screen (where the real image is formed) will be \( 75 - x \) cm.
- The focal length \( f \) of the lens is given as 12 cm.

### Step 2: Apply the Lens Formula
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