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Tetrahedron Faces

Age 7 to 11
Challenge Level Yellow starYellow starYellow star
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Some children from Carr head Primary School sent in this solution.  It's actually a solution to a different question being asked - they worked on not having to use each of the 4 colours for each arrangement. We have included it here as it's shows a really good piece of work. Here is what they wrote:-

I am writing to you because we think that we (9 kids from Carr Head Primary School) have found a solution for your tetrahedron question and here's how we did it. Has anybody else found a solution yet?
First we split into 3 different groups,  Elliott, Ben B and Oliver were in one group but we started by making a 3D tetrahedron. Second we coloured them with all the colours properly, then we numbered the faces.
Next we put the first letters of the colours (B,G,Y,R) and put the numbers of the faces
B G Y R
1 2  3 4
Then swapped them around like 1,3,2,4 but we noticed that we were rotating it. An answer was 24 but that was wrong.
Here is the table that works. This doesn't rotate and the answer would be 10 because you only have 1 blue all the time and it needed 4 of all the colours added up.
 

If you try this, then do send us what you find out.


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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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