document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=475581>Question 475581</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dear math teacher, \r<BR>\n" );
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document.write( "Would you help me explain how to convert r! to r? \r<BR>\n" );
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document.write( "Here is the problem I am talking about:\r<BR>\n" );
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document.write( "Given nPr=3024 and nCr=126, find r. \r<BR>\n" );
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document.write( "nCr=nPr/(r!)<BR>\n" );
document.write( "126=3024/(r!)<BR>\n" );
document.write( "r!=24<BR>\n" );
document.write( "Here is where I get stuck because I don't know how to take factorial to an integer. The textbook's answer lists r=4 as an answer but I do not understand how they converted r! to r. Would you please explain it to me?\r<BR>\n" );
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document.write( "Thank you very much for your help and time. \r<BR>\n" );
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document.write( "Sincerely, \r<BR>\n" );
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document.write( "I.   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #326112 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=326112\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> nPr/nCr=r! --> r!= 3024/126= 24 --> r=4 ....--> r!=24=4*3*2*1=4!\r<BR>\n" );
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document.write( "nC4= 126 --> n·(n-1)·(n-2)·(n-3)/24= 126 --> n·(n-1)·(n-2)·(n-3)= 3024<BR>\n" );
document.write( "--> n=9 it is a solution </SPAN>\n" );
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