document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=84209>Question 84209</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 3.	Jane invested some amount at the rate of 12% simple interest and some other amount at the rate of 10% simple interest. She received yearly interest of $130. Randy also invested in the same scheme, but he interchanged the amounts invested, and received $4 more as interest. How much amount did each of them invest at different rates? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #60633 by </B><A HREF=/tutors/aboutme.mpl?userid=sofiyacherni><B>sofiyacherni(99)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sofiyacherni><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=60633\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 3. Jane invested some amount at the rate of 12% simple interest and some other amount at the rate of 10% simple interest. She received yearly interest of $130. Randy also invested in the same scheme, but he interchanged the amounts invested, and received $4 more as interest. How much amount did each of them invest at different rates?\r<BR>\n" );
document.write( "\n" );
document.write( "Here is how you should approach this problem<BR>\n" );
document.write( "Say she invested x dollars at 12%, to represent % as a number divide % by 100, so 12% is .12. Say she invested y dollars at 10%, so .10. From this she earned 130 dollars. So you have your first equation<BR>\n" );
document.write( ".12x+.10y=130<BR>\n" );
document.write( "Next if you interchange amounts invested and add 4 dollars to earnings you have sencond equation<BR>\n" );
document.write( ".10x+.12y=134<BR>\n" );
document.write( "so use substitution to solve a system of equations\r<BR>\n" );
document.write( "\n" );
document.write( "(1)   .12x+.10y=130<BR>\n" );
document.write( "(2)   .10x+.12y=134\r<BR>\n" );
document.write( "\n" );
document.write( "so, from (2) .1x+.12y=134<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28134-.12y%29%2F.1 ALIGN=MIDDLE  ALT=\"x=%28134-.12y%29%2F.1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(3) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1340-1.2y ALIGN=MIDDLE  ALT=\"x=1340-1.2y\"   DISABLED_style= \"max-width:90%; height:auto;\" > now sub this in (1) in place of x, you get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.12%281340-1.2y%29%2B.1y=130 ALIGN=MIDDLE  ALT=\".12%281340-1.2y%29%2B.1y=130\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=160.8-.144y%2B.1y=130 ALIGN=MIDDLE  ALT=\"160.8-.144y%2B.1y=130\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-.044y=-30.8 ALIGN=MIDDLE  ALT=\"-.044y=-30.8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=700 ALIGN=MIDDLE  ALT=\"y=700\"   DISABLED_style= \"max-width:90%; height:auto;\" > now plug this value into (3), you get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1340-1.2%28700%29 ALIGN=MIDDLE  ALT=\"x=1340-1.2%28700%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1340-840 ALIGN=MIDDLE  ALT=\"x=1340-840\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=500 ALIGN=MIDDLE  ALT=\"x=500\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "So JANE invested $500 at 12% and $700 at 10% and<BR>\n" );
document.write( "RANDY invested $700 at 12% and $500 at 10% <BR>\n" );
document.write( "Good luck<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );