document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=367067>Question 367067</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, Please help!\r<BR>\n" );
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document.write( "There are 21 English books and 19 French Books. How can these books be arranged on a shelf where no 2 french books are placed together? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #261717 by </B><A HREF=/tutors/aboutme.mpl?userid=Jk22><B>Jk22(389)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Jk22><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=Jk22><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=261717\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Step 1 : we put between French books 1 English books, hence we now have 19+18 = 37 books.<BR>\n" );
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document.write( "Step 2 : we put the 3 remaining English books at any place, this makes : 38*39*40 possibilities but we have to get rid of the order, hence we get : <BR>\n" );
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document.write( "N = 38*39*40/6 = 38*13*20 = 260*38 = 9880 possibilities.\r<BR>\n" );
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