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Tri.'s

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

There are lots of answers to this, depending on what questions you choose to ask. Here is what a teacher from  Tudor Grange Academy Solihull wrote:-  

Attached is my copy of as many answers to the Tri's task as possible. I used it with a year 8 class to get them to practice measuring angles, and to get them doing more problem solving and thinking laterally as part of my angles scheme of work. I got them to compete to see who could find the most different solutions, then got them thinking about whether the triangles were scalene, isosceles, right-angled, thinking about why none of them were equilateral, which of them were right angled, and discussing why using a protractor to measure the angles can be much less accurate than using mathematical methods to calculate the exact angles.

   

Thanks a lot for those they're great and show some good signs of creativity.


Have a go yourself, and if you discover anything interesting then email primary.nrich@maths.org. Please don't worry that your solution is not "complete" - we'd like to hear about anything you have tried. Teachers - you might like to send in a summary of your children's work.

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Tessellating Triangles

Can you make these equilateral triangles fit together to cover the paper without any gaps between them? Can you tessellate isosceles triangles?

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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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