document.write( "Question 696929: It is known that there are two defective items in a group of ten.One item is selected and then a second without replacing the first item.
\n" ); document.write( "What is the probability that
\n" ); document.write( "i)both items are good
\n" ); document.write( "ii)the second one is defective
\n" ); document.write( "iii)both are defective \n" ); document.write( "
Algebra.Com's Answer #429490 by stanbon(75887)\"\" \"About 
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It is known that there are two defective items in a group of ten.One item is selected and then a second without replacing the first item.
\n" ); document.write( "What is the probability that
\n" ); document.write( "i)both items are good
\n" ); document.write( "# of ways to succeed: 8C2 = 28
\n" ); document.write( "# of possible outcomes: 10C2 = 45
\n" ); document.write( "P(2 good) = 28/45
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\n" ); document.write( "ii)the second one is defective
\n" ); document.write( "# of ways to succeed: 8*2 + 9*1 = 25
\n" ); document.write( "# of possible outcomes: 45
\n" ); document.write( "P(2nd is defective) = 25/45 = 5/9
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\n" ); document.write( "iii)both are defective
\n" ); document.write( "# of ways to succeed: 2C2 = 1
\n" ); document.write( "# of possible: 45
\n" ); document.write( "P(2 defective) 1/45
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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