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New Math Challenge Celebrates 10 Years of Cheryl's Birthday!

3/31/2025

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Summary

Story summary

A decade ago, "Cheryl's birthday problem" captured hearts and minds as a viral math puzzle in the Guardian. Initially designed for teens, it ignited a series of nearly 250 puzzles since 2015. To mark this special anniversary, creator Joseph Yeo returns with an exciting new challenge featuring unique one-digit numbers, inviting everyone to join the fun!

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Story summary

A decade ago, "Cheryl's birthday problem" captured hearts and minds as a viral math puzzle in the Guardian. Initially designed for teens, it ignited a series of nearly 250 puzzles since 2015. To mark this special anniversary, creator Joseph Yeo returns with an exciting new challenge featuring unique one-digit numbers, inviting everyone to join the fun!