document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=368260>Question 368260</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Quality Control: A factory produces fuses, which are packaged in boxes of 10.  Three fuses are selected at random from each box for inspection.  The box is rejected if at least one of these three fuses is defective.  What is the probability that a box containing five defective fuses will be rejected?\r<BR>\n" );
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document.write( "The answer is 11/12 which = .917, but how is it done?\r<BR>\n" );
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document.write( "Thank you in advanced... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #262412 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=262412\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The experiment follows a hypergeometric distribution:  there are 5 good fuses and 5 bad fuses.<BR>\n" );
document.write( "1st case, 1 bad and 2 good fuses:  # of ways is C(5,1)*C(5,2) = 50.<BR>\n" );
document.write( "2nd case, 2 bad and 1 good fuse:  # of ways is C(5,2)*C(5,1) = 50.<BR>\n" );
document.write( "3rd case, 3 bad and 0 good fuse: # of ways is C(5,3)*C(5,0) = 10.<BR>\n" );
document.write( "The number of ways of choosing any 3 out of 10 fuses in a box is C(10,3) = 120.<BR>\n" );
document.write( "Therefore the probability is (50+50+10)/120 = 110/120 = 11/12. </SPAN>\n" );
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