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More Numbers in the Ring

Age 5 to 7
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More Numbers in the Ring printable sheet

Three blank squares joined in a ringBefore doing this problem, it would be a good idea to look at Ring a Ring of Numbers.

Change the ring so that there are only three squares.
Can you place three different numbers in them so that their differences are odd?
Can you make the differences even?
What do you notice about the sum of each pair in each case?

Try with different numbers of squares around the ring.
What happens with 5 squares? 6 squares?
What do you notice?

This problem is based on an idea taken from "Apex Maths Pupils' Book 2" by Ann Montague-Smith and Paul Harrison, published in 2003 by Cambridge University Press.

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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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