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Let's Investigate Triangles

Age 5 to 7
Challenge Level Yellow star
Primary curriculum
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Thank you to everybody who sent in their solutions to this activity. We received lots of good ideas about which triangles were possible or impossible to make. 

Zoe from Halstead Preparatory School in the UK sent us this picture:

Well done for checking every possible combination, Zoe! Zoe says that the longest side of a triangle has to be shorter than the other two sides put together. I wonder why?

We also had this picture sent in from Vivienne and Georgy at Halstead Preparatory School:

Well done for using practical resources to check each triangle! These pictures show really clearly why each triangle is either possible or not possible.

We also had similar solutions sent in from Viren KS and from Ariana, Ayda, Ishita and Rhea from Halstead Preparatory School. Thank you all for sending us your ideas.

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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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