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Tetrahedron Faces

Age 7 to 11
Challenge Level Yellow starYellow starYellow star
  • Problem
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One face of a regular tetrahedron is painted blue and each of the remaining faces are painted using one of the colours red, green or yellow.

tetrahedra


How many different possibilities are there, if we count those that just differ by a rotation as the same?
How many different possibilities would there be if the tetrahedron was irregular?

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Construct-o-straws

Make a cube out of straws and have a go at this practical challenge.

Matchsticks

Reasoning about the number of matches needed to build squares that share their sides.

Little Boxes

How many different cuboids can you make when you use four CDs or DVDs? How about using five, then six?

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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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