document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=691679>Question 691679</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how long would it take to double an investment of 1000 at 9 percent 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 #426815 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=426815\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">     how long would it take to double an investment of 1000 at 9 percent compounded quarterly?<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Use:<BR>\n" );
document.write( "A = P(1+i/n)^(nt)<BR>\n" );
document.write( "where<BR>\n" );
document.write( "A is amount after time t (2P)<BR>\n" );
document.write( "P is the principal (P)<BR>\n" );
document.write( "i is the interest per year (.09)<BR>\n" );
document.write( "n is the times compounded during the year (4)<BR>\n" );
document.write( "t is number of years (what we're looking for)<BR>\n" );
document.write( ".<BR>\n" );
document.write( "A = P(1+i/n)^(t/n)<BR>\n" );
document.write( "2P = P(1+.09/4)^(4t)<BR>\n" );
document.write( "2 = (1+.09/4)^(4t)<BR>\n" );
document.write( "2 = (1.0225)^(4t)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%281.0225%2C2%29 ALIGN=MIDDLE  ALT=\"log%281.0225%2C2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 4t<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%281.0225%2C2%29%2F4 ALIGN=MIDDLE  ALT=\"log%281.0225%2C2%29%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = t<BR>\n" );
document.write( "7.79 years = t<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );