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'Peri the Winkle' printed from https://nrich.maths.org/
Peri the winkle starts at the origin $(0,0)$ and slithers anticlockwise around a semicircle with centre at $(4,0)$.
Peri then slides anticlockwise around a second semicircle with centre at $(6,0)$.
Finally, Peri slides clockwise around a third semicircle with centre at $(3,0)$.
Where does Peri end this expedition?
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