A sphere, a cylinder and a cone are of the same radius and same height. Find the ratio of their curved surface.

Explanation

To find the ratio of the curved surface areas of a sphere, a cylinder, and a cone that have the same radius (R) and height (H), we will follow these steps:

### Step 1: Identify the dimensions
Let the radius of the sphere, cylinder, and cone be \( R \). Since the sphere has a height of \( 2R \), the height of the cylinder and cone will also be \( 2R \).

### Step 2: Calculate the curved surface area of the sphere
The formula for the curved surface area (CSA) of a sphere is:
\[
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