document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=614921>Question 614921</A>: <I><SPAN STYLE=\"word-break: break-all;\"> There are 20 students in a class, 10 who are girls, and 10 who are boys. The teacher is choosing 4 of these students to be on a committee. What is the probability that there will be at least one girl and at least one boy? Use complementary counting. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #386766 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=386766\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are 20 students in a class, 10 who are girls, and 10 who are boys. The teacher is choosing 4 of these students to be on a committee. What is the probability that there will be at least one girl and at least one boy? Use complementary counting.<BR>\n" );
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document.write( "Number of ways to fail:<BR>\n" );
document.write( "Choose 4 boys: 1 way<BR>\n" );
document.write( "Choose 4 girls: 1 way<BR>\n" );
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document.write( "# of possible groups of 4: 20C4 = 4045<BR>\n" );
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document.write( "P(at lest one boy and at least one girl) = 1 - 2/4045 = 4043/4035<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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