document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1103814>Question 1103814</A>: <I><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "How long&#8203; (in years and&#8203; months) will it take for an investment to double at <BR>\n" );
document.write( "9<BR>\n" );
document.write( "9&#8203;% compounded&#8203; monthly? </SPAN>\n" );
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document.write( "The annual interest rate is 9%, or 0.09; the monthly interest rate is 0.09/12 = 0.0075.  The monthly growth factor is then 1+.0075 = 1.0075.<br><BR>\n" );
document.write( "We want to know how many months it takes for the overall growth factor to be 2, so that the original investment doubles.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281.0075%29%5En+=+2 ALIGN=MIDDLE  ALT=\"%281.0075%29%5En+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n%2Alog%281.0075%29+=+log%282%29 ALIGN=MIDDLE  ALT=\"n%2Alog%281.0075%29+=+log%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n+=+log%282%29%2Flog%281.0075%29+=+92.77 ALIGN=MIDDLE  ALT=\"n+=+log%282%29%2Flog%281.0075%29+=+92.77\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "It will take 93 months for the investment to double in value; or, in years and months, 7 years and 9 months. </SPAN>\n" );
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