quad inside quad, compare diagonals' sum (2023 Novosibirsk Oral Geo Oly 7.5)
Source:
September 4, 2023
geometrygeometric inequality
Problem Statement
One convex quadrilateral is inside another. Can it turn out that the sum of the lengths of the diagonals of the outer quadrilateral is less than the sum of the lengths of the diagonals of the inner?