document.write( "Question 1183692: A lot consists of 20 defective and 80 non-defective items from which two items
\n" ); document.write( "are chosen without replacement. Events A & B are defined as A = the first item
\n" ); document.write( "chosen is defective, B = the second item chosen is defective
\n" ); document.write( "a. What is the probability that both items are defective?
\n" ); document.write( "b. What is the probability that the second item is defective?
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Algebra.Com's Answer #814116 by Edwin McCravy(20055)\"\" \"About 
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A lot consists of 20 defective and 80 non-defective items from which two items
\n" ); document.write( "are chosen without replacement. Events A & B are defined as A = the first item
\n" ); document.write( "chosen is defective, B = the second item chosen is defective
\n" ); document.write( "a. What is the probability that both items are defective?
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document.write( "(20/100)(19/99) = 19/495 = 0.038383838... = 3.8383...%

\n" ); document.write( "b. What is the probability that the second item is defective
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document.write( "(20/100)(19/99)+(80/100)(20/99) = 1/5 = 0.2 = 20%\r\n" );
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document.write( "What's interesting here, that Ikleyn missed, is that if we drew n items,\r\n" );
document.write( "where n =1,2,...,100 the probability that the nth item drawn is defective is\r\n" );
document.write( "always 1/5 or 20%. \r\n" );
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document.write( "Edwin
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