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For younger learners

  • Early Years Foundation Stage

Triangle Pin-down

Age 7 to 11
Challenge Level Yellow starYellow starYellow star
  • Problem
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Have you looked at the angles in the triangles drawn? It might help to draw in some radii and work out angles from the centre.

How will you record the triangles you can make? You might like to print off these sheets if you're not using the interactivity:
Sheet of three-peg boards
Sheet of four-peg boards
Sheet of five-peg boards
Sheet of six-peg boards
Sheet of seven-peg boards
Sheet of eight-peg boards
Sheet of nine-peg boards

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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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