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How confident? Even with an even distribution of birthdays it's possible to have a billion people in the room that don't share your birthday. Very unlikely, but
by isostatic 7y ago
How confident? Even with an even distribution of birthdays it's possible to have a billion people in the room that don't share your birthday. Very unlikely, but as there's only about 20 million people with your birthday, and 7 billion without, it's quite doable.
- dwaltrip 7y ago"Very unlikely" is a severe understatement. With only 100k people, the odds of no one else having your birthday is 10^-120. With a million people, it is 10^-1192. And with a billion people... apparently, there are over a million zeroes between the decimal place and the first non-zero number. That is a pretty damn small probability. Here is the code I used in python 3: from decimal import Decimal print((Decimal(364) / Decimal(365)) ** num_people)
- isostatic 7y agoquite, hence "how confident" There's other things as play. Imagine you, born on July 15th, walked into a room with 1000 people. You'd be fairly confident someone will be born on July 15? What if I then told you it was the annual astrology get together of Capricorns?
- dwaltrip 7y agoSure, but you did say "even distribution".