document.write( "Question 823139: \"7% of al switches produced are defective. if 200 switches are selected at random, what us the probability that more than 20 will be defective?\"
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Algebra.Com's Answer #495293 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( "\"7% of al switches produced are defective. if 200 switches are selected at random, 
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document.write( "what us the probability that more than 20 will be defective?\" 
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document.write( "BINOMIAL Distribution P(x) = nCx*  
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document.write( "where p and q are the probabilities of success and failure respectively. 
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document.write( "In this case p = .07 & q = .93 & n = 200   nCx = 
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document.write( " P(20) =(200C20)(.07)^20(.93)^180   Or binompdf(200, .07, 20)on calculator
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document.write( "Recommend using Your TI calculator for cumulative probabilities
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document.write( "and/or stattrek.com as an excellent reference.  
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document.write( " P(x>20) = 1 - P(x ≤ 20)  = 1 - binomcdf(200, .07, 20) on a Ti calculator
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document.write( "Without a Calculator: 1 - [ P(0) + P(1) + P(2) .... + P(20)]
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document.write( "Tedious, but can be done.
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document.write( "Again: stattrek.com is an excellent reference (also has calculators)
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