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For younger learners

  • Early Years Foundation Stage

Four Triangles Puzzle

Age 5 to 11
Challenge Level Yellow star
Primary curriculum
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources


If you cut a square diagonally from corner to corner you get four right-angled isosceles triangles.

How many different shapes can you make by fitting the four triangles back together?

You may only fit long sides to long sides and short sides to short sides.

The whole length of the side must be joined.

You might like to record what you do.



You could use this interactivity to try out your ideas.

Click on the grey triangles to make new pieces.
You can rotate them by dragging the corners.



Printable NRICH Roadshow resource.

You may be interested in the other problems in our I Wonder... What If...? Feature.

Related Collections

  • Back to LTHC resources

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If you had 36 cubes, what different cuboids could you make?

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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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