<PRE><B>Question 765252</B>
Suppose 20 chips numbered 1-20 are put in a box.. Suppose a chip is drawn WITH REPLACEMENT repeatedly. 
What is the probability that a prime (2,3,5,7.11,13,17,19) will be first taken on the 7th draw?
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Pattern::: nnnnnnp
There are 8 primes and 12 non-prime numbers
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P(1st prime on 7th draw) = (12/20)^6*(8/20) = (3/5)^6*(2/5) = 0.0187
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Cheers,
Stan H.
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