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## 'Magic Octahedron' printed from http://nrich.maths.org/

The diagram show the net of a regular octahedron.

In a magic octahedron, the four numbers on the faces that meet at a vertex add up to make the same total for every vertex. If the letters $F, G, H, J$ and $K$ are replaced with the numbers $2$, $4$, $6$ and $8$, in some order, to make a magic octahedron, what is the value of $G + J$?

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*This problem is taken from the UKMT Mathematical Challenges.*

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