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By inscribing a circle in a square and then a square in a circle find an approximation to pi. By using a hexagon, can you improve on the approximation?
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Age 16 to 18 Challenge Level:
 |
A length of thin wire ($L$ ) binds together two
cylindrical welding rods, whose radii are $R$ and $r$ , by passing all
the way around them both.
Find $L$ in terms of $R$ and $r$. |
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NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.