Question 212074
P(having a certain birthdate) = 1/365
Binomial Problem: 3 of 6 have the same birthdate.
P(3 of 6) = 6C3(1/365)^3*(364/365)^3 
= 20(365)^(-3)(0.997)^(3)
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= 0.00000040792...
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Cheers,
Stan H. 
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