document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=398208>Question 398208</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help in trying to understand exactly what formula I need to find the answer to this problem. \r<BR>\n" );
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document.write( "A real estate investor bought acreage for $7200. After reselling three-fourths of the acreage at a profit of $30 per acre, she recovered the $7200. How many acres did she sell? \r<BR>\n" );
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document.write( "Thank you for your help.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #282166 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=282166\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A real estate investor bought acreage for $7200. After reselling three-fourths of the acreage at a profit of $30 per acre, she recovered the $7200. How many acres did she sell?<BR>\n" );
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document.write( "Let original price per acre be \"x\"<BR>\n" );
document.write( "Let the # of acres be \"y\"<BR>\n" );
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document.write( "unit price*# of acres = total price paid<BR>\n" );
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document.write( "xy = 7200 dollars<BR>\n" );
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document.write( "When the price is x+30 and # of acres is (3/4)y you get:<BR>\n" );
document.write( "(x+30)(3/4)y = 7200<BR>\n" );
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document.write( "Solve the system:<BR>\n" );
document.write( "xy = 7200<BR>\n" );
document.write( "(x+30)(3/4)y = 7200<BR>\n" );
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document.write( "y = 7200/x<BR>\n" );
document.write( "Substitute for \"y\" and solve for \"x\":<BR>\n" );
document.write( "(x+30)(3/4)(7200/x) = 7200<BR>\n" );
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document.write( "(x+30)(1800/x) = 2400<BR>\n" );
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document.write( "(x+30)(3) = 4x<BR>\n" );
document.write( "3x+90 = 4x<BR>\n" );
document.write( "x = 90 acres (original number of acres)<BR>\n" );
document.write( "(3/4)x = (3/4)90 = 67.5 (# of acres she sold)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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