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Doughnut

Age 7 to 11
Challenge Level Yellow star
  • Problem
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How can you cut a doughnut into eight equal pieces with only three cuts of a knife?


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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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