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A Right Charlie

Age 7 to 11
Challenge Level Yellow starYellow star
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Charlie's house number is a three-digit square number.

This number when reversed is also a square and is Charlie's telephone extension at work.

His car registration number is  a four-digit square number and is formed from his house number by repeating the right hand digit.

What is Charlie's house number?


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Cuisenaire Squares

These squares have been made from Cuisenaire rods. Can you describe the pattern? What would the next square look like?

Making Boxes

Cut differently-sized square corners from a square piece of paper to make boxes without lids. Do they all have the same volume?

Special 24

Find another number that is one short of a square number and when you double it and add 1, the result is also a square number.

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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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