The radius of curvature of a convex mirror is 40 cm. Find its focal length.

Explanation

To find the focal length of a convex mirror given its radius of curvature, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Information**:
- The radius of curvature (R) of the convex mirror is given as 40 cm.

2. **Understand the Relationship**:
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