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What is clock arithmetic?

November 4, 2026 · 10 min

Show notes

Did you know that sometimes 11 plus 3 equals exactly 2?! It sounds impossible, but you actually use this crazy math every single day without even realizing it! Welcome to the mind-bending world of clock arithmetic! Instead of numbers going on forever in a boring straight line, what if they wrapped round and round in a circle? After 12 o'clock comes 1 again! Days of the week and months of the year do the exact same thing. In 1801, a brilliant 24-year-old mathematician from Germany named Carl Friedrich Gauss wrote a massive book proving that these spinning numbers follow their very own tidy rules. He called it modular arithmetic, and the secret star of the show is the "remainder"—the part left over after you make a full circle! Today, this same looping math isn't just for telling time. It is the secret superpower that checks barcodes at the grocery store and protects secret text messages on your phone! Join Mira and Finn as they spin into the amazing, endless loops of wrapping math!

All episodes of Maths for Kids / Maths is Not Boring: The Kids Maths Podcast

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