<PRE><B>Question 534794</B>
A box contains 50 balls numbered from 1 to 50. If 10 balls are drawn with replacement, what is the probability that at least two of them have the same number? 
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P(at least 2 have same #) = 1 - P(no 2 have the same number)
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Examine P(no 2 have same number)
# of ways to succeed: 50C10 
# of possible outcomes: 50^10
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P(no 2 have same number) = 50C10/50^10 = 1.05x10^-7
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So, P(at least 2 have same #) = 1 - (1.05x10^-7)
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Cheers,
Stan H. </PRE>