document.write( "Question 670644: Hello,
\n" ); document.write( "I'm working on an assignment for my Stats class. I am stumped on how to calculate this question. I believe it has to do with Binomial Distribution but I'm not 100% positive. \r
\n" ); document.write( "\n" ); document.write( "In a market study for Zellers, a researcher found that 70% of customers are repeat customers. If 12 customers are selected at random, find the probability of getting.
\n" ); document.write( "a. Exactly 9 of them are repeat customers
\n" ); document.write( "b. At least 9 of them are repeat customers
\n" ); document.write( "c. At most 9 of them are repeat customers\r
\n" ); document.write( "\n" ); document.write( "Thank you.
\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #417039 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,	
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document.write( "Binomial Distribution;  Yes  (repeat or not repeat)
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document.write( " p = .70, q = .30  and n = 12
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document.write( " P(x = 9) = 12C9(.70)^9(.30)^3    binompdf(12,.70,9)
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document.write( " P(x ≥ 9 ) = P(x=9) + P(x=10) + P(x=11) + P(x=12)     1 - binomcdf(12,.70,8)
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document.write( " P(x ≤ 9)  = P(x=0) + P(x=1) + P(x=2).... + P(x=9)    binomcdf(12,.70.9) \n" );
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