document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=113986>Question 113986</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bob invested $20,000, part at 14% and part at 13%.  If the total interest at the end of the year is $2,720, how much did he invest at 14%? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #82954 by </B><A HREF=/tutors/aboutme.mpl?userid=BrittanyM><B>BrittanyM(80)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=BrittanyM><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=82954\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We can solve this by setting up a sysrem:\r<BR>\n" );
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document.write( "Since we know the the total investment was 20,000, 100% of both rates is written as\r<BR>\n" );
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document.write( "x + y = 20,000\r<BR>\n" );
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document.write( "And since the given rates of the investment, 14% and 13%, yielded 2,720 we have\r<BR>\n" );
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document.write( "0.14x + 0.13y = 2,720\r<BR>\n" );
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document.write( "From the first equation, let <BR>\n" );
document.write( "x = -y + 20,000\r<BR>\n" );
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document.write( "So let's plug this into the second equation:\r<BR>\n" );
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document.write( "0.14(-y + 20,000) + 0.13y = 2,720<BR>\n" );
document.write( "-0.14y + 2,800 + 0.13y = 2,720<BR>\n" );
document.write( "-0.01y + 2,800 = 2,720<BR>\n" );
document.write( "-0.01y = -80<BR>\n" );
document.write( "y = 8,000\r<BR>\n" );
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document.write( "Now, we can subtract our y value from 20,000 in order to find x:\r<BR>\n" );
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document.write( "x = -y + 20,000<BR>\n" );
document.write( "x = -8,000 + 20,000<BR>\n" );
document.write( "x = 12,000 </SPAN>\n" );
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