Henry Ernest Dudeney/Puzzles and Curious Problems/350 - The Keys and Ring/Solution

Puzzles and Curious Problems by Henry Ernest Dudeney: $350$

The Keys and Ring

Colonel Crackham the other day produced a ring and two keys, as here shown,

cut out of a solid piece of cardboard, without a break or join anywhere.

Solution

First cut out the keys and ring in one piece, as here shown.

Now cut only half through the cardboard along the eight little dark lines,

and similarly cut half through on the eight little dotted lines on the other side of the cardboard.

Then insert a penknife and split the card below the four little squares formed by these lines,

and the keys will come apart with the keys loose on the ring and no join.

Sources

• 1932: Henry Ernest Dudeney: Puzzles and Curious Problems ... (previous) ... (next): Solutions: $350$. -- The Keys and Ring
• 1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Answers: $531$. The Keys and Ring