document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1111059>Question 1111059</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Josh wants to double his $20,000 in 6 years.  What interest rate does Josh need?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #726081 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=726081\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Rule of 72 would say 72/6=12% interest<BR>\n" );
document.write( "40000=20000(1+r)^6<BR>\n" );
document.write( "2=(1+r)^6<BR>\n" );
document.write( "ln 2=6 ln (1+r)<BR>\n" );
document.write( "0.693=6 ln(1+r)<BR>\n" );
document.write( "0.693/6=0.1155=ln(1+r)<BR>\n" );
document.write( "raise everything to e power<BR>\n" );
document.write( "1.122=1+r<BR>\n" );
document.write( "r=0.122 or 12.2% interest </SPAN>\n" );
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