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IMO 1969 - Longlist Problems Question 9

IMO Shortlist · IMO 1969 - Longlist Problems

Question 9

(BUL 3) One hundred convex polygons are placed on a square with edge of length $38$ cm. The area of each of the polygons is smaller than $\pi$ cm², and the perimeter of each of the polygons is smaller than $2\pi$ cm. Prove that there exists a disk with radius $1$ in the square that does not intersect any of the polygons.