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Squaring the Circle

Age 11 to 14
Challenge Level Yellow starYellow star
  • Problem
  • Getting Started
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Plenty to keep you busy here.

You can see a full quarter of the circle and you can extrapolate from this fairly accurately.

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Square Pegs

Which is a better fit, a square peg in a round hole or a round peg in a square hole?

Bull's Eye

What fractions of the largest circle are the two shaded regions?

Blue and White

Identical squares of side one unit contain some circles shaded blue. In which of the four examples is the shaded area greatest?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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