document.write( "Question 65432: HI, i need help with this problem:
\n" ); document.write( "A new shipment of 9 VCRs, which will be offered at a very low price, are delivered to a store. Unknow to the manager, 4 of the VCRs are defective.
\n" ); document.write( "Determine the probability that at least one of the first 3 VCRs sold is defective. Express your answer to the nearest tenth of one percent.: \n" ); document.write( "
Algebra.Com's Answer #45965 by Edwin McCravy(20056)\"\" \"About 
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A new shipment of 9 VCRs, which will be offered at a very low price, are\r\n" );
document.write( "delivered to a store. Unknow to the manager, 4 of the VCRs are defective.\r\n" );
document.write( "Determine the probability that at least one of the first 3 VCRs sold is\r\n" );
document.write( "defective. Express your answer to the nearest tenth of one percent.: \r\n" );
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document.write( "We use the complement event.\r\n" );
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document.write( "P(choosing a bad VCR) = 4/9\r\n" );
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document.write( "P(choosing a good VCR) = 1 - P(choosing a bad VCR) = 5/9\r\n" );
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document.write( "So\r\n" );
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document.write( "P(choosing at least one defective in the three) = \r\n" );
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document.write( "1 - P(choosing 3 good VCR's) = \r\n" );
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document.write( "1 - P(choosing 1st good AND choosing 2nd good AND choosing 3rd good) =\r\n" );
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document.write( "1 - P(choosing 1st good) times\r\n" );
document.write( "          P(choosing 2nd good given that the 1st one was good) times\r\n" );
document.write( "                P(choosing 3rd good given that the 1st and 2nd were good) \r\n" );
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document.write( "= 1 - (5/9)(4/8)(3/7) = 1 - 5/42 = 37/42 = .880952381 = 88% approximately\r\n" );
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document.write( "Edwin
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