document.write( "Question 1014038: There are 1000 components in a box of which 10 are known to be
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\n" ); document.write( "b)neither is defective
\n" ); document.write( "c)just one is defective \n" ); document.write( "

Algebra.Com's Answer #630440 by Edwin McCravy(20060) $\"\"$ $\"About$

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There are 1000 components in a box of which 10 are known to be
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document.write( "Probability that the first one is defective = 10/1000 = 1/100.\r\n" );
document.write( "Probability that the second one is defective, given that the first\r\n" );
document.write( "was defective is is 9/999 = 1/111.\r\n" );
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document.write( "P(both are defective) = (10/1000)(9/999) = (1/100)(1/111) = 1/11100\r\n" );
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\n" ); document.write( "b)neither is defective
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document.write( "There are 990 non-defective ones.\r\n" );
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document.write( "Probability that the first one is not defective = 990/1000 = 99/100.\r\n" );
document.write( "Probability that the second one is not defective, given that the \r\n" );
document.write( "first was not defective is is 989/999.\r\n" );
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document.write( "P(neither is defective) = (99/100)(989/999) = 10879/11100\r\n" );
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\n" ); document.write( "c)just one is defective
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document.write( "Probability that the first one is defective is 10/1000 or 1/100\r\n" );
document.write( "Probability that the second one is not defective given that \r\n" );
document.write( "the first was defective is 990/999 = 110/111\r\n" );
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document.write( "That's (1/100)(110/111) = 11/1110\r\n" );
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document.write( "Probability that the first one is not defective is 990/1000 or \r\n" );
document.write( "99/100\r\n" );
document.write( "Probability that the second one is defective given that the \r\n" );
document.write( "first was not defective is 10/999 \r\n" );
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document.write( "That's also = 11/1110\r\n" );
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document.write( "The probability that one or the other will occur is the sum of \r\n" );
document.write( "those two probabilities:\r\n" );
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document.write( "11/1110 + 11/1110 = 11/555\r\n" );
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document.write( "Edwin

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