<PRE><B>Question 566666</B>
What is the probablity that a seven-digit telephone number has one or more repeated digits? Assume no one digit is more likely than another to be used. In addition, the leading digit cannot be zero.
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Pattern: ------- where lead digit is not zero
Total number: 9*10^6 = 9 million with repeates
Total number with no repeats: 9*9*8*7*6*5*4 = 544320
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P(1 or more repeated digits) = 1 - (544320]/9000000) = 0.9395
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Cheers,
Stan H.
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