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The Birthday Problem

Posted by Michael Gold - April 13, 2009 - Mathematics

After discussing the solution to the Birthday Problem, someone at Queen’s University in Cananda says:

The more people there are in a group, the higher the chances of any two people having a birthday match. The probability is:

70% for 30 people
90% for 41 people
95% for 47 people
over 99% for 57 people.

Dr. Math also discusses how to solve the birthday problem.

Dr. Reese of the Mathematics, Science, and Technology Education program at the University of Illinois at Urbana-Champagne allows you to run your own simulation.

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