document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1204860>Question 1204860</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 11 books are to be stored in a shelf where 4 books can be put vertically, so they are all as easily accessible, and 6 books can be piled-up, so the most used ones are on the top.<BR>\n" );
document.write( "(a) In how many ways the books can be put in vertical positions?<BR>\n" );
document.write( "Your answer is : \r<BR>\n" );
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document.write( "(b) In how many ways the books can be piled-up?<BR>\n" );
document.write( "Your answer is : \r<BR>\n" );
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document.write( "(c) In how many ways the books can be put in both positions?<BR>\n" );
document.write( "Your answer is : \r<BR>\n" );
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document.write( "out of 11 books only 10 will be on the shelf.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #841386 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=841386\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The wording of your post leaves open the possibility of very different interpretations of the problem.<br><BR>\n" );
document.write( "(a) 4 books on the shelf vertically can be arranged in 4! = 24 different ways.<br><BR>\n" );
document.write( "(b) 6 books in a pile can be arranged in 6! = 720 different ways.<br><BR>\n" );
document.write( "(c) The 10 books together, 4 vertically and 6 in a pile, can be arranged in 24*720 = 17280 different ways.<br><BR>\n" );
document.write( "If the intended problem involves which of the 11 books are stored vertically or in the pile, then of course that is a completely different problem.<br><BR>\n" );
document.write( "If my answers are not what you expected, then re-post the problem, defining it clearly....<br><BR>\n" );
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