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An opportunity to think about the total number of possible
combinations and then use some deductive reasoning.
A surprising result - we can find the number with so few clues.
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.
Label the joints and legs of these graph theory caterpillars so that the vertex sums are all equal.