For a normal relaxed eye, a simple microscope is rated as 3X. What will be the rating of a microscope for a relaxed farsighted eye whose near point is 50 cm.

Explanation

To solve the problem, we need to determine the rating of a microscope for a relaxed farsighted eye whose near point is 50 cm. We will use the concept of magnifying power (M) and the relationship between the near point and focal length of the microscope.

### Step-by-Step Solution:

1. **Understand the given information**:
- For a normal relaxed eye, the near point (d) is 25 cm.
- The magnifying power (M) for a normal relaxed eye is given as 3X.
- For the farsighted eye, the near point (d') is 50 cm.
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