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For younger learners

  • Early Years Foundation Stage

Doughnut

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Student Solutions
  • Teachers' Resources

Oliver (Christchurch Cathedral School, UK) has shown his solution clearly in a diagram.

Plan view Side View

Josh (Ampthill, UK) has used words to give the same solution:

Cut in quarters vertically at the top at right angles and then cut horizontally.

Sam (Nanyang Primary School, Singapore) came up with a different approach:

I think that the solution is:

  1. You cut the doughnut into halves.
  2. Then you cut it into quarters.
  3. Put all the 4 pieces into a stack and cut into halves.
  4. You will get 8 equal pieces using 3 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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