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Twisting has the effect of adding 1: $$x\rightarrow x + 1$$ Turning transforms any number into the negative of its reciprocal: $$x\rightarrow -\frac{1}{x}$$ Starting at zero, the first five moves: Twist, twist, twist,
turn,
twist
produces:$$0, 1, 2, 3, -\frac{1}{3}, \frac{2}{3}$$
Can you continue from there and then return to zero? You can use the reciprocal button on a calculator ($\frac{1}{x}$ ) to help with the calculations.
Take another look at the video. Can you spot the strategy they used to get back to 0?