document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1053737>Question 1053737</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A square farm contains as many acres as there are boards in the fence enclosure.    The fence is 7 boards high, and each board is 8.25 ft. in length.  Determine acres in the farm.\r<BR>\n" );
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document.write( "My partial attempt:\r<BR>\n" );
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document.write( "x = number of boards = number of acres.\r<BR>\n" );
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document.write( "x/4 = number of boards on one side.\r<BR>\n" );
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document.write( "43560 = square ft. in acre.\r<BR>\n" );
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document.write( "Unsure how to continue.  Thanks. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #668943 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=668943\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let the side of the farm=x ft.<BR>\n" );
document.write( "The area is x^2 sq. ft.<BR>\n" );
document.write( "The number of boards along a side is (x/8.25)*7=(7x/8.25)<BR>\n" );
document.write( "The total number of boards is then (28x/8.25).<BR>\n" );
document.write( "That equals the number of acres.<BR>\n" );
document.write( "The number of acres of the farm is x^2/43560.<BR>\n" );
document.write( "Therefore, (x^2/43560)=(28x/8.25)<BR>\n" );
document.write( "cross-multiply<BR>\n" );
document.write( "8.25x^2=1219680x<BR>\n" );
document.write( "8.25x^2-1219680x=0<BR>\n" );
document.write( "x(8.25x-1219680)=0<BR>\n" );
document.write( "x=147840 feet<BR>\n" );
document.write( "x^2/43560 is 501760 acres or 784 sq miles (28 miles on a side)<BR>\n" );
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document.write( "Each side has 28 miles*5280 feet/mile, or 147840 feet<BR>\n" );
document.write( "divide that by 8.25 feet/board, and need 17920 boards just to line it.<BR>\n" );
document.write( "But there are 4 sides, so 71680 boards.<BR>\n" );
document.write( "And there are 7 boards stacked, so that is 71680*7=501760 boards.  Checks<BR>\n" );
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