document.write( "Question 408149: A quality control engineer tests the quality of produced computers Suppose that 5% of computers have defects and defects occur independently of each other.\r
\n" ); document.write( "\n" ); document.write( "(a) Find the probability of exactly 3 defective computers in a shipment of 20.
\n" ); document.write( "(b) Find the probability that the engineer has to test atleast 5 computers in order to find 2 defective ones. \n" ); document.write( "

Algebra.Com's Answer #287604 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 = .05 & q = .95 
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document.write( "nCx = \r
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document.write( "a) P(exactly 3 of 20 being defective computers) = 1140(.05)^3(.95)17 = .0596
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document.write( "(b) P( test at least 5 computers to find 2 defective ones)
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document.write( " P = 1 - (.05)^0*(.95)^5 + 5*(.05)^1*(.95)^4 = .0226  \n" );
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