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Three Triangles

Age 7 to 11
Challenge Level Yellow star
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We haven't received many solutions to this task. Pedro from Mount Kelly in the UK noticed:

They all add up to 180 degrees and two sets of three triangles add up to 360 degrees.

Well spotted, Pedro! I wonder what would happen if we used a quadrilateral instead of a triangle?

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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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