document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1122247>Question 1122247</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Paige Turner loves finite mathematics. She has 4 books about probability and 3 books about matrices. \r<BR>\n" );
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document.write( "How many ways can she place these books on the same shelf in a row if: \r<BR>\n" );
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document.write( "a) there are no restrictions. \r<BR>\n" );
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document.write( "b) the books about probability are next to each other but the others could be anywhere on the shelf. \r<BR>\n" );
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document.write( "c) books are organized by their topic (probability books are next to each other and matrix books are next to each other).  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #738320 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=738320\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Paige Turner — love it!\r<BR>\n" );
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document.write( "a)  7! = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28+5040+%29+ ALIGN=MIDDLE  ALT=\"highlight%28+5040+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "b) Treat the 4 probability books like a unit, that gives 4!=24 ways of arranging.  However, for each one of these arrangements, the 4 probability books can be arranged in 4! ways, therefore 4! * 4! = 24 * 24 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+highlight%28576%29+ ALIGN=MIDDLE  ALT=\"+highlight%28576%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c)  4!*3!*2 = 24*6*2 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28+288%29+ ALIGN=MIDDLE  ALT=\"highlight%28+288%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >   (*2 because each subject can be on left or right)  <BR>\n" );
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