document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=474912>Question 474912</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How long will it take for an investment to double in value, if the annual interest rate is 10% and interest is compounded every 6 months? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #325658 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=325658\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How long will it take for an investment to double in value, if the annual interest rate is 10% and interest is compounded every 6 months<BR>\n" );
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document.write( "compound interest formula: A=P(1+i)^n, A=value of investment after n periods, P=initial investment, i=interest rate per period, n=number of periods.<BR>\n" );
document.write( "For given problem:A/P=(1+i)^n,A/P=2, i=.10/2=.05<BR>\n" );
document.write( "2=(1+.05)^n<BR>\n" );
document.write( "2=(1.05)^n<BR>\n" );
document.write( "take log of both sides<BR>\n" );
document.write( "log2=nlog(1.05)<BR>\n" );
document.write( "n=log2/log(1.05)<BR>\n" );
document.write( "n=14.2 6-mo periods or 7.1 years </SPAN>\n" );
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