document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=122552>Question 122552</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An investor received $1400 interest per annum from a sum of money, with part of it invested at 10% and the remainder at 7% simple interest. This investor found that if she interchanged the amounts she had invested she could  increase her return by $90 per annum. Calculate the total amount invested. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #90003 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=90003\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A) .1x+.07y=1400<BR>\n" );
document.write( "B) .07x+.1y=1490<BR>\n" );
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document.write( "A) <BR>\n" );
document.write( ".1x=1400-.07y<BR>\n" );
document.write( "x=14000-.7y multiply each side by 10.<BR>\n" );
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document.write( "B) <BR>\n" );
document.write( ".07(14000-.7y)+.1y=1490<BR>\n" );
document.write( "980-.049y+.1y=1490<BR>\n" );
document.write( ".051y=510<BR>\n" );
document.write( "y=10000<BR>\n" );
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document.write( "A)<BR>\n" );
document.write( ".1x+.07(10000)=1400<BR>\n" );
document.write( ".1x+700=1400<BR>\n" );
document.write( ".1x=700<BR>\n" );
document.write( "x=7000<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "B)<BR>\n" );
document.write( ".07(7000)+.1(10000)=1490<BR>\n" );
document.write( "490+1000=1490 true<BR>\n" );
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document.write( "Ed </SPAN>\n" );
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