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Cheese Cutting

Age 16 to 18
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This is a difficult visualisation problem to tackle, not least because is it very difficult to create a physical model with which it is possible to experiment with the slicing. Visualisation is thus crucially required.


The problem can be attempted at various levels, from having an educated guess at the answer to providing a proof of the maximum possible number of pieces.

If solvers are unable to prove the maximum number of pieces they should certainly be encouraged to describe their best effort at a slicing as clearly and convincingly as possible. Try to establish the existence of an upper bound on the number of pieces.

In practice, the solver may be able to spot the answer quite quickly, but providing an explanation of the answer may be very hard. Solvers should be encouraged to try to explain their answer as clearly as possible in words if a sound mathematical argument cannot intially be provided.




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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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