document.write( "Question 436898: (This problem has 4 different questions.)
\n" ); document.write( "Twenty-five percent of the employees of a large company are minorities. A random sample of 7 employees is selected.
\n" ); document.write( "A) what is the probability that the sample contains 4 minorities?
\n" ); document.write( "B) what is the probability that the sample contains fewer than 2 minorities?
\n" ); document.write( "C) what is the probability that the sample contains exactly 1 non-minority?
\n" ); document.write( "D) what is the expected value of minorities in the sample? \n" ); document.write( "

Algebra.Com's Answer #302268 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "Note: The probability of x successes in n trials is: 
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document.write( "P = nCx*  where p and q are the probabilities of success and failure respectively. 
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document.write( "In this case p = .25 and q = .75  and n = 7
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document.write( "nCx = 
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document.write( "P( sample contains 4 minorities) = 35(.25)^4(.75)^3
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document.write( "P(sample < than 2 minorities)= P(0)+P(1) =  (.75)^7 + 7(.25)(.75)^6
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document.write( "P(sample contains exactly 1 non-minority) = 7(.25)(.75)^6\r
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document.write( "expected value of minorities in the sample = .25*7 = 1.75 \n" );
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