document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=345770>Question 345770</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I'm trying to figure out how this answer was derived from this problem. I understand how to do the Permutation problems but not the combinatorics\r<BR>\n" );
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document.write( "C (17, 4)  the answer given was 35. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #247256 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=247256\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I understand how to do the Permutation problems but not the combinatorics <BR>\n" );
document.write( "C(17, 4) the answer given was 35.<BR>\n" );
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document.write( "Formula: C(n,r) = n!/(n-r)!r!<BR>\n" );
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document.write( "C(17,4) = 17!/[13!*4!] = (17*16*16*14)/(1*2*3*4) = 2380<BR>\n" );
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document.write( "The answer is definately not 35.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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