document.write( "Question 375850: USA Today reports that about 25% of all prison parolees become repeat offenders. Alice is a social worker whose job is to counsel people on parole. Let us say success means a person does not become a repeat offender. Alice has been given a group of four parolees.\r
\n" ); document.write( "\n" ); document.write( "(a) Find the probability P(r) of r successes ranging from 0 to 4.
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Algebra.Com's Answer #267631 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 = .75 & q = .25
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document.write( "nCx = 
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document.write( "P(0) = .25^4 = .0039
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document.write( "P(1) = 4(.75)(.25)^3 = .0469       4C1 = 4
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document.write( "P(2) = 6(.75)^2(.25)^2 = .2109     4C2 = 6
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document.write( "P(3) = 4(.75)^3(.25)1 = .4219      4C3 = 4
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document.write( "P(4) = (.75)^4 = .3164\r
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document.write( ".75*4 = 3  will not be repeat offenders
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