Which three-dimensional figure has the greatest number of faces?

A prism with an n-sided base has n rectangular side faces plus 2 bases, so a hexagonal prism has 6 + 2 = 8 faces. A pyramid with an n-sided base has n triangular side faces plus 1 base, so an octagonal pyramid has 8 + 1 = 9 faces. A rectangular prism has 6 faces, and a pentagonal pyramid has 6, so the octagonal pyramid has the greatest number.

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