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MathNet 2013 Question 26

Math Olympiad Vault · MathNet 2013

Question 26

Several small circles are arranged inside a unit circle $\Gamma$. The sum of the perimeters of all these small circles is not less than $\pi$ and none of them includes the center of $\Gamma$.
Prove that there exists a concentric with $\Gamma$ circumference intersecting at least two of these small circles.

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