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For younger learners

  • Early Years Foundation Stage

Magic W Wrap Up

Age 16 to 18
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions

To make a Magic W you have to put the numbers 1, 2, ...,9, one in each circle, so that each row of three numbers has the same total. Experiment to find as many different magic totals as you can using the interactivity from the Magic W problem.

Prove that if you have a Magic W and you replace each of the numbers by 10 minus that number then the new W is also magic. What will its magic total be?

Prove that you cannot form a Magic W with a total of 12 or less. Also prove that you cannot form a Magic W with a total of 18 or more.

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

Magic Caterpillars

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

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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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