document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=128843>Question 128843</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help with this question.\r<BR>\n" );
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document.write( "An intial investment of $5000 earns 8% interst, compounded continuously.  What will the investment be worth in 15 years? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #94232 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=94232\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> For continuous compounding remember PERT.\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;\" >, where P is the original principal, r is the rate per time period, and t is the number of time periods.  You have an annual rate and a number of years - that matches, so just use the numbers, remembering to convert 8% to a decimal fraction (0.08).  And e is the base of the natural logarithms, approx 2.718...\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=5000%2Ae%5E%28.08%2A15%29 ALIGN=MIDDLE  ALT=\"A=5000%2Ae%5E%28.08%2A15%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Using the Windows calculator in scientific mode:\r<BR>\n" );
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document.write( "0.08 * 15 = 1.2 <BR>\n" );
document.write( "Check the INV box, then press the \"ln\" button, then * 5000 = 16600.58\r<BR>\n" );
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document.write( "This works because the inverse (INV box checked) of the natural log (ln) is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=e%5Ex ALIGN=MIDDLE  ALT=\"e%5Ex\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "This answer also makes sense because using the rule of 72, we know that an 8% investment should double every 9 years (actually a little faster than that with continuous compounding), so having the money more than triple in 15 years is reasonable.\r<BR>\n" );
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