Henry Ernest Dudeney/Modern Puzzles/146 - The Cardboard Box

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Modern Puzzles by Henry Ernest Dudeney: $146$

The Cardboard Box
If I have a closed cubical cardboard box, by running the penknife along seven of the twelve edges (it must always be seven)
I can lay it out in one flat piece in various shapes.
Dudeney-Modern-Puzzles-146.png
Thus, in the diagram, if I pass the knife along the darkened edges and down the invisible edge indicated by the dotted line, I get the shape $A$.
Another way of cutting produces $B$ or $C$.
It will be seen that $D$ is simply $C$ turned over, so we will not call that a different shape.
Now, how many shapes can be produced?


Click here for solution

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