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Number Differences

Age 7 to 11
Challenge Level Yellow star
Primary curriculum
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Number Differences printable sheet


You might like to try A Ring of Numbers and More Rings of Numbers before this problem.

Place the numbers from 1 to 9 in the squares below so that the difference between joined squares is odd. (You must use each of the numbers once.)

 

Can you find some other ways to do this?

Can you put the numbers in the squares so that the difference between joined squares is even? Explain your answer.

What general statements can you make about odd and even numbers?

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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