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A Mean Tetrahedron

Age 11 to 14
Challenge Level Yellow starYellow starYellow star
  • Problem
  • Student Solutions

Solutions to this puzzle came in from Shauneen from Our Lady's Grammar School , Newry; Claire and Amy of Madras College, St Andrew's; Nicola and Rosie of Maidstone Grammar School for Girls and Chris, Sarah, Jack, Laura, Jan and Michael from Necton Middle School, Norfolk . An equivalent (dual) solution to the one illustrated is obtained by swapping the numbers at the vertices with the numbers on the faces.


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What are the possible dimensions of a rectangular hallway if the number of tiles around the perimeter is exactly half the total number of tiles?

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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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