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

Puzzles and Curious Problems by Henry Ernest Dudeney: $198$

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.

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.

Sources

• 1932: Henry Ernest Dudeney: Puzzles and Curious Problems ... (previous) ... (next): Geometrical Problems: Patchwork Puzzles: $198$. -- The Patchwork Cushion
• 1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Geometrical Problems: Dissection Puzzles: $359$. The Patchwork Cushion