This website contains problems from math contests. Problems and corresponding tags were obtained from the Art of Problem Solving website.

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Found problems: 2

1982 Polish MO Finals, 6

Prove that the sum of dihedral angles in an arbitrary tetrahedron is greater than $2\pi$

1983 Polish MO Finals, 6

Prove that if all dihedral angles of a tetrahedron are acute, then all its faces are acute-angled triangles.