7ᵗʰ Iranian Geometry Olympiad (Intermediate) P5
Posted: Sat Dec 12, 2020 4:18 pm
Find all numbers $n \ge 4$ such that there exists a convex polyhedron with exactly $n$ faces, whose all faces are right-angled triangles.
(Note that the angle between any pair of adjacent faces in a convex polyhedron is less than $180^{\circ}$.)
(Note that the angle between any pair of adjacent faces in a convex polyhedron is less than $180^{\circ}$.)