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.

It Must Be 2000

Age 7 to 11
Challenge Level

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.