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Math Help - An intriguing polyhedron case

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    An intriguing polyhedron case

    Prove that in a convex polyhedron, the number of faces with odd number of sides cannot be odd.

    Any ideas on how to tackle that one ?
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    I don't understand the question as stated. Isn't a face of a polygon the same as a side? Do you mean edge instead of side or something?
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  3. #3
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    No idea. Perhaps this'll help you:
    Convex Polyhedron
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    Quote Originally Posted by atreyyu View Post
    Prove that in a convex polyhedron, the number of faces with odd number of sides cannot be odd.

    Any ideas on how to tackle that one ?
    Hint: Each edge of the polyhedron is shared between two faces. So the total number of edges of the polyhedron is half of the total number of sides on all the faces.
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