document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=206325>Question 206325</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A mother wants to invest $12,000 for her sons future education. She invests a portion of the money into a bank CD which 4% and the remainder in a savings bond that earns 7%. If the total interest earned after one year is $720.00 how much was invested into the CD?? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #155897 by </B><A HREF=/tutors/aboutme.mpl?userid=mickclns><B>mickclns(59)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mickclns><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=155897\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let c be the amount invested in the CD.  The amount invested in a bond is $12,000 - c<BR>\n" );
document.write( "The interest earned on the CD is .04c.  The interest earned on the bond is .07(12000 - c). <BR>\n" );
document.write( "The equation, then, for the total interest earned is:<BR>\n" );
document.write( " .04c + .07(12000 - c) = 720<BR>\n" );
document.write( ".04c + 840 - .07c = 720  Combining the terms with c in them and subtracting 840 from both sides:<BR>\n" );
document.write( "-.03c = -120  Dividing both sides by -3, we have<BR>\n" );
document.write( ".01c = 40  Multiplying both sides by 100 (same as dividing by .01 = 1/100), we have<BR>\n" );
document.write( "c = 4000 which is the answer desired. </SPAN>\n" );
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