document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=609327>Question 609327</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what is the value of nCr when r=n </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #383684 by </B><A HREF=/tutors/aboutme.mpl?userid=math-vortex><B>math-vortex(648)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math-vortex><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=math-vortex><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=383684\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hi, there--<BR>\n" );
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document.write( "There are (at least) to ways you can think about this. First, we have a formula for nCr.\r<BR>\n" );
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document.write( "nCr = n! / (r!(n-r)!)<BR>\n" );
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document.write( "Since n=r, we can substitute n for r in the formula.<BR>\n" );
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document.write( "nCn = n! / (n!(n-n)!)<BR>\n" );
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document.write( "Simplify.<BR>\n" );
document.write( "nCn = n! / (n! 0!)<BR>\n" );
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document.write( "n! over n! is 1. By definition 0! is also 1. So nCn = 1 when n=r.<BR>\n" );
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document.write( "Another way to think about this is to remember what combinations mean. How many ways can I choose  r objects from a group of n objects. (Order does not matter.) When n=r, I'm choosing all the objects. Order does not matter, so there is only one way to choose.<BR>\n" );
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document.write( "I hope this helps. Feel free to email if you still have questions about this.<BR>\n" );
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document.write( "Ms.Figgy<BR>\n" );
document.write( "math.in.the.vortex<BR>\n" );
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