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Witch's Hat

Age 11 to 16
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Thanks to Cubes, Aisling and Brandon for their ideas on how to make a wizard's hat or a witch's hat.  Cubes suggested cutting out two triangles and sticking them together.  Aisling and Brandon both suggested rolling a piece of paper into a cone.

Either of these methods would work to make a pointy hat.  

But there is a better way to make a conical hat.

Alice worked through this problem and found a very surprising answer. She sent in some work which you can find here.

She only found the tallest wizard's hat, can you do something similar to find the witch's hat, fez or top hat?

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This article for students gives some instructions about how to make some different braids.

Celtic Knotwork Patterns

This article for pupils gives an introduction to Celtic knotwork patterns and a feel for how you can draw them.

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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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