document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1147968>Question 1147968</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The floor of a rectangular room is completely covered with square tiles. The room is 9 tiles long and 5 tiles wide. Find the number of tiles that touch the walls or door of the room. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #769318 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=769318\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 24<BR>\n" );
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document.write( "The workout:\r<BR>\n" );
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document.write( "Along the perimeter:  2*9 + 2*5 = 28  but subtract 4 because each corner is counted twice, leaving 24.\r<BR>\n" );
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document.write( "More generally...\r<BR>\n" );
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document.write( "To see the pattern, imagine the room has only 4 tiles in a 2x2 arrangment: the perimeter is 2*2+2*2 = 8, and subtracting 4 leaves 4.\r<BR>\n" );
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document.write( "For a 3x3 configuration: 2*3+2*3 = 12, 12-4 = 8  (clearly correct as only the center tile does not touch a wall or door, and 3*3-1 = 8).\r<BR>\n" );
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document.write( "etc.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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