Solution

(related to Problem: The Folded Cross)

First, fold the cross along the dotted line $A B$ in Fig. $1.$ You then have it in the form shown in Fig. $2.$

a145a

Next, fold it along the dotted line $C D$ (where $D$ is, of course, the center of the cross), and you get the form shown in Fig. $3.$ Now take your scissors and cut from $G$ to $F,$ and the four pieces, all of the same size and shape, will fit together and form a square, as shown in Fig. $4.$

a145b


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References

Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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