Stage: 3 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!
Have a go yourself, and if you discover anything interesting, e-mail us to tell us what you've done!
smartphone. Selecting and using information. Games. Interactivities. physics. Factors and multiples. Addition & subtraction. Investigations. Working systematically. Visualising.
Published November 2000.
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