Henry Ernest Dudeney/Puzzles and Curious Problems/198 - The Patchwork Cushion

by : $198$

 * The Patchwork Cushion
 * A lady had $20$ pieces of silk, all of the same triangular shape and size.
 * She found that four of these would fit together and form a perfect square, as in the illustration.


 * Dudeney-Puzzles-and-Curious-Problems-198.png


 * How was she to fit together these $20$ pieces to form a perfectly square patchwork cushion?
 * There must be no waste, and no allowance need be made for turnings.