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So It's 28

Age 5 to 7
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
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We had very few ideas sent in but it seems that most pupils went on to the other challenge focussed on $28$: $28$ and It's Onwards and Upwards.

Matthew wrote the following and sent in the picture to go with it:


I used $28$ tessellating crosses, which are on the file. Looks quite cool. The scary thing is, after copying and pasting $28$ crosses (having just made them a random size), I, co-incidentally, couldn't fit any more than $28$ on the page ...
Kanumilli

and Emma wrote:


I got grid paper and drew $14$ squares that were touching and drew a line diagonally through every square. I got $28$ triangles because I had $14$ squares and split them in $2$ which made $28$ because $14+14=28$. That is how I got $28$ 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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