The radii of two circles are `19` cm and `9` cm respectively. Find the radius of the circle which has circumference equal to the sum of the circumferences of the two circles.

Explanation

To solve the problem, we need to find the radius of a circle whose circumference is equal to the sum of the circumferences of two given circles with radii of 19 cm and 9 cm.

### Step-by-Step Solution:

1. **Identify the given values**:
- Radius of the first circle (r1) = 19 cm
- Radius of the second circle (r2) = 9 cm

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