Think it’s possible to make a paper ring expand to twice its size without attaching or inserting anything to it? No, you say? Paper doesn’t stretch, after all. Well, give it a try anyway.
Task: make a ring from a strip of paper and, cutting it lengthwise, end up with a ring whose circumference is twice the size of the first ring.
How it’s done: before attaching the ends of the paper strip, turn one end over so it faces inside out.
Attach the ends as shown.
Start cutting the ring lengthwise.
Cut to the end.
Now see what has resulted. You have in your hands not two rings, but one large one!
You can turn this puzzle into a magic trick. You’ll need to use a long strip of paper and attach the ends quickly so that no one notices how you’ve done it. Then cut quickly and confidently. Your audience will be impressed by seeing you do the impossible!