document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=887210>Question 887210</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The shipment of 10 television sets contain 3 defectives sets . In hw many ways can a dealer purchase 4 of these sets and recieve at least 2 of the defectives sets </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #536463 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=536463\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the 10 tv sets include 7 good and 3 defective<BR>\n" );
document.write( "to get at least 2 defective in a set of 4, the dealer needs to get sets of 4 tv's that include exactly 2 defectives each and sets of 4 tv's that include exactly 3 defectives each.\r<BR>\n" );
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document.write( "each set of 2 defectives will include 2 good and 2 defectives.<BR>\n" );
document.write( "each set of 3 defectives will include 1 good and 3 defectives.\r<BR>\n" );
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document.write( "the number of ways you can get a set of 2 defectives and 2 good is equal to:<BR>\n" );
document.write( "3C2 * 7C2\r<BR>\n" );
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document.write( "the number of ways you can get a set of 3 defectives and 1 good is equal to:<BR>\n" );
document.write( "3C3 * 7C1\r<BR>\n" );
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document.write( "3C2 * 7C2 = 3 * 21 = 63\r<BR>\n" );
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document.write( "3C3 * 7C1 = 1 * 7 = 7\r<BR>\n" );
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document.write( "total number of ways to get sets of 4 that include at least 2 defectives each is equal to 63 + 7 = 70.\r<BR>\n" );
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document.write( "nCx formula is equal to n! / (x! * (n-x)!\r<BR>\n" );
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document.write( "for example:\r<BR>\n" );
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document.write( "7C2 = 7! / (2! * 5!) = (7*6*5*4*3*2*1) / (2*1*5*4*3*2*1) = 21\r<BR>\n" );
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document.write( " </SPAN>\n" );
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