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Counting Triangles

Age 11 to 14
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
Triangles are formed by joining the vertices of a skeletal cube.

How many different types of triangle are there?

How many triangles altogether?

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Draw a square. A second square of the same size slides around the first always maintaining contact and keeping the same orientation. How far does the dot travel?

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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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