document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=344440>Question 344440</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If 4 factories in a group of 20 factories in a community are violatig environmental regulations and 6 are randomly selected for inspection, what is the probability that none of the violators will be selected?\r<BR>\n" );
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document.write( "What formula do I even begin to solve this problem with? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #247741 by </B><A HREF=/tutors/aboutme.mpl?userid=jrfrunner><B>jrfrunner(365)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jrfrunner><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=jrfrunner><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=247741\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let N=event the chosen factory is a non violator<BR>\n" );
document.write( "each outcomes probability is dependent on what was selected previously<BR>\n" );
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document.write( "P(selecting 6 at random and getting none of the violators)=P(NNNNNN)<BR>\n" );
document.write( "= (16/20)*(15/19)*(14/18)*(13/17)*(12/16)*(11/15) = 0.2066<BR>\n" );
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document.write( "this probability could also be written as\r<BR>\n" );
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document.write( "C(4,0)*C(16,6)/C(20,6)  basically # ways choosing 0 of the 4 violators times # ways of choosing 6 nonviolators out of 16 nonviolators divided by the # ways of selecting 6 factories out of 20\r<BR>\n" );
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