Wheels on Wheels
Imagine two wheels of exactly the same size touching each other. One of them is fixed but the other one can roll around the fixed wheel.
Question
How many complete rotations does it require for the one outer wheel to roll completely around the fixed wheel and back to the start?  Answer
Mind Games
BBC Links
Challenges from series three
Challenges from series two
What kind of thinker are you?
Challenges from GCSE Bitesize
Test your memory
External Link
Marcus du Sautoy's official website
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