In a room of 23 people, there is a 50% chance two share a birthday.

Wacky WorldNumbers & Maths

It feels wrong because we think of our own birthday, but there are 253 possible pairs among 23 people.

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Pi has been calculated to trillions of digits.Pingala described binary numbers over 2,000 years ago.<span class="aj-year">1920</span>A googol is 1 followed by 100 zeros.