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Snake Coils

Age 7 to 11
Challenge Level Yellow star
  • Problem
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We received a few solutions to this problem but most children made a mistake somewhere in their working. This seems to be a difficult problem to solve! Some children talked about using string or strips of paper to help them.

Mary from the UK sent in this table:

This is very clearly laid out, Mary. What do you think Mary means by 'length of each coil'?

What patterns are there in this table?

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How can you cut a doughnut into 8 equal pieces with only three cuts of a knife?

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Grandma found her pie balanced on the scale with two weights and a quarter of a pie. So how heavy was each pie?

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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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