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8 Methods for Three by One

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Age 14 to 18
Challenge Level
Thank you to Michael for sending a very clear and comprehensive solution. You can read it here. Well done!


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.
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