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The Guardian - UK

Science

Alex Bellos

Can you solve it? The pals that broke the internet, ten years on

Albert, Bernard and Cheryl. Maybe. — Albert, Bernard and Cheryl. Maybe. Photograph: izusek/Getty Images/iStockphoto

Ten years ago I published a maths olympiad question from Singapore on the Guardian website, and it changed my life.

‘Cheryl’s birthday problem’ went viral. Its unexpected success led to the birth of this column in May 2015. And here we are, almost 250 puzzles later.

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