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Twin Chute-swapping Sudoku

Age 14 to 18
Challenge Level Yellow star
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Find the positive integer solutions of the equation (1+1/a)(1+1/b)(1+1/c) = 2

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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.

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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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