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enter image description here

Your task is to convert a diamond shape monomino that is made from aluminum foil into an x-shape pentomino (see figures). You may fold the monomino and make one straight cut with a pair of scissors. After the cut, you will unfold the foil and align the separate pieces. The alignment should produce the X-shape shown above, using all pieces of the original monomino. How can this be done without any additional tools?

Note: No overlapping and pieces can be flipped but not need to be attached or joined.

TSLF
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1 Answers1

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A solution, and on request an asymmetric solution:

Symmetric:
Cut A=B=C=D to X after folding the blue dotted line in picture 2.
Pieces 1 to 4 are now cut off, and can be moved to make the cross.
note: The initial folds are the 1/4 - 3/4 lines
Asymmetric:
Fold A to X3, D to X1, B to X4
('line' to cut is now X1,X2,X3)
Fold X1X2 to X3X4 and then p to q
cut X4 to X3 [enter image description here

Retudin
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