document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=662331>Question 662331</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the time required for an investment of 5000 dollars to grow to 7200 dollars at an interest rate of 7.5 percent per year, compounded quarterly. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #412155 by </B><A HREF=/tutors/aboutme.mpl?userid=sravanik2005><B>sravanik2005(14)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sravanik2005><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=412155\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A = P(1+ r/n)^nt<BR>\n" );
document.write( "here P is principal amount=5000<BR>\n" );
document.write( "r=interest rate as decimal=0.075<BR>\n" );
document.write( "and n=number of times the interest is compounded per year=4<BR>\n" );
document.write( "t= number of years=? and A=amount of money accumulated after t years, including interest=7200 dollars<BR>\n" );
document.write( "substitute these values in that formula<BR>\n" );
document.write( "7200=5000(1+0.075/4)^(4t)<BR>\n" );
document.write( "7200/5000=1.01875^4t => 1.01875^4t=36/25<BR>\n" );
document.write( "ln(1.01875)^4t=ln (36/25)<BR>\n" );
document.write( "4t(ln 1.01875)=ln(36/25)<BR>\n" );
document.write( "=>t= ln(36/25)/(4ln 1.01875)=4.91 that is approximately 5 years  </SPAN>\n" );
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