document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=219496>Question 219496</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How long does it take your money in your savings account to double at 8% interest rate using the formula A=Pe^rt ?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #165051 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=165051\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=Pe%5E%28rt%29 ALIGN=MIDDLE  ALT=\"A=Pe%5E%28rt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the continuous compounding interest formula.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2P=P%2Ae%5E%280.08%2At%29 ALIGN=MIDDLE  ALT=\"2P=P%2Ae%5E%280.08%2At%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=2P ALIGN=MIDDLE  ALT=\"A=2P\"   DISABLED_style= \"max-width:90%; height:auto;\" > (since we want to double our investment), and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=0.08 ALIGN=MIDDLE  ALT=\"r=0.08\"   DISABLED_style= \"max-width:90%; height:auto;\" > (note: 0.08 is the decimal equivalent of 8%).\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282P%29%2FP=e%5E%280.08%2At%29 ALIGN=MIDDLE  ALT=\"%282P%29%2FP=e%5E%280.08%2At%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=800 ALIGN=MIDDLE  ALT=\"800\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2=e%5E%280.08%2At%29 ALIGN=MIDDLE  ALT=\"2=e%5E%280.08%2At%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Reduce.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%282%29=ln%28e%5E%280.08%2At%29%29 ALIGN=MIDDLE  ALT=\"ln%282%29=ln%28e%5E%280.08%2At%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Take the natural log of both sides.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%282%29=0.08%2At%2Aln%28e%29 ALIGN=MIDDLE  ALT=\"ln%282%29=0.08%2At%2Aln%28e%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Pull down the exponent using the identity <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28x%5Ey%29=y%2Aln%28x%29 ALIGN=MIDDLE  ALT=\"ln%28x%5Ey%29=y%2Aln%28x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%282%29=0.08%2At%2A1 ALIGN=MIDDLE  ALT=\"ln%282%29=0.08%2At%2A1\"   DISABLED_style= \"max-width:90%; height:auto;\" > Evaluate <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28e%29 ALIGN=MIDDLE  ALT=\"ln%28e%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1 ALIGN=MIDDLE  ALT=\"1\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%282%29=0.08%2At ALIGN=MIDDLE  ALT=\"ln%282%29=0.08%2At\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.693147=0.08%2At ALIGN=MIDDLE  ALT=\"0.693147=0.08%2At\"   DISABLED_style= \"max-width:90%; height:auto;\" > Evaluate <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%282%29 ALIGN=MIDDLE  ALT=\"ln%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.693147 ALIGN=MIDDLE  ALT=\"0.693147\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.693147%2F0.08=t ALIGN=MIDDLE  ALT=\"0.693147%2F0.08=t\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.08 ALIGN=MIDDLE  ALT=\"0.08\"   DISABLED_style= \"max-width:90%; height:auto;\" > to isolate 't'\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8.664338=t ALIGN=MIDDLE  ALT=\"8.664338=t\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.693147%2F0.08 ALIGN=MIDDLE  ALT=\"0.693147%2F0.08\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8.664338 ALIGN=MIDDLE  ALT=\"8.664338\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=8.664338 ALIGN=MIDDLE  ALT=\"t=8.664338\"   DISABLED_style= \"max-width:90%; height:auto;\" > Rearrange the equation.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=8.66 ALIGN=MIDDLE  ALT=\"t=8.66\"   DISABLED_style= \"max-width:90%; height:auto;\" > Round to the nearest hundredth.\r<BR>\n" );
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document.write( "So it will take about 8.66 years for an initial investment to double if it is compounded continuously at an interest rate of 8%.<BR>\n" );
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