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# Magic W

The sum of the numbers 1 to 9 is 45 and four rows of 13 add up to 52. How do you make up the extra 7?

See also Olympic Magic.

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Age 14 to 16

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The sum of the numbers 1 to 9 is 45 and four rows of 13 add up to 52. How do you make up the extra 7?

See also Olympic Magic.

Given the nets of 4 cubes with the faces coloured in 4 colours, build a tower so that on each vertical wall no colour is repeated, that is all 4 colours appear.

Explore some of the different types of network, and prove a result about network trees.

Label the joints and legs of these graph theory caterpillars so that the vertex sums are all equal.