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Twisting has the effect of adding 1: $$x\mapsto x + 1$$ Turning transforms any number into the negative of its reciprocal: $$x\mapsto -\frac{1}{x}$$ Starting at zero, these five moves: Twist, twist, twist, turn, twist
produce:$$0, 1, 2, 3, -\frac{1}{3}, \frac{2}{3}$$
Can you continue from there and then return to zero? You might find it helpful to record each step in a table.
Take another look at the video.
The team use a strategy to help them get back to zero.
Can you figure out how they decide when to stop twisting and start turning?
If you want to have a go at the trick for yourself, but don't have enough people or skipping ropes, you can also perform the tangling and untangling process using a small piece of card and two pieces of string.
The team use a strategy to help them get back to zero.
Can you figure out how they decide when to stop twisting and start turning?
If you want to have a go at the trick for yourself, but don't have enough people or skipping ropes, you can also perform the tangling and untangling process using a small piece of card and two pieces of string.
