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It Must Be 2000

Age 7 to 11
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There are lots of answers to this problem, depending on what questions you choose to ask.

Have a go yourself, and if you discover anything interesting, e-mail us to tell us what you've done! Please don't worry that your solution is not "complete" - we'd like to hear about anything you have tried. Teachers - you might like to send in a summary of your children's work.

You may also like

Sometimes We Lose Things

Well now, what would happen if we lost all the nines in our number system? Have a go at writing the numbers out in this way and have a look at the multiplications table.

Nim-like Games

A collection of games on the NIM theme

A Story about Absolutely Nothing

This article for the young and old talks about the origins of our number system and the important role zero has to play in it.

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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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