document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=75521>Question 75521</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0495105716/algebrahomeworkh>Elementary algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A sum $2300 is invested, part of it at 10% interest and the reaminder at 12%.  If the interest earned by the 12% investment is $100 more than the intrest earned by the 10% investment, find the amount invested at each rate?\r<BR>\n" );
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document.write( "Thanks! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #54226 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=54226\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  \r<BR>\n" );
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document.write( "Let x=amount invested at 12%\r<BR>\n" );
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document.write( "Then (2300-x)=amount invested at 10%\r<BR>\n" );
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document.write( "0.12x=interest earned on the 12% investment (for 1 year. (I=PRT))\r<BR>\n" );
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document.write( "0.10(2300-x)=interest earned on the 10% investment\r<BR>\n" );
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document.write( "So, we are told that if we add $100 to the interest on the 10% investment, it will equal the interest earned on 12% investment.\r<BR>\n" );
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document.write( "Then our equation to solve is:\r<BR>\n" );
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document.write( "0.10(2300-x)+100=0.12x  get rid of parens\r<BR>\n" );
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document.write( "230-0.10x+100=0.12x  add 0.10x to both sides\r<BR>\n" );
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document.write( "230-0.10x+0.10x+100=0.12x+0.10x  collect like terms\r<BR>\n" );
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document.write( "330=0.22x  divide both sides by 0.22\r<BR>\n" );
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document.write( "x=$1500----------------amount invested at 12%\r<BR>\n" );
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document.write( "$2300-x=$2300-$1500=$800--------------------------amount invested at 10%\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "interest from 12% investment=1500*0.12=$180<BR>\n" );
document.write( "interest from 10% investment=$800*0.10=$80<BR>\n" );
document.write( "$80+$100=$180<BR>\n" );
document.write( "$180=$180\r<BR>\n" );
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document.write( "Hope this helps----ptaylor\r<BR>\n" );
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document.write( " </SPAN>\n" );
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