A concave mirror forms a real image three times larger than the object on a screen. The object and screen are moved until the image becomes twice the size of the object. If the shift of the object is 6cm, find the shift of screen.

Explanation

To solve the problem step by step, we will follow the given information and apply the mirror formula along with the magnification concept.

### Step 1: Understand the Given Information
We know that:
- A concave mirror forms a real image that is three times larger than the object.
- The object and screen are moved until the image becomes twice the size of the object.
- The shift of the object is 6 cm.

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