document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=676947>Question 676947</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An investment of $10000 is guaranteed to have a return of $25000 in 20 years. If the interest is compounded semi-annually, what is the annual interest rate? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #420639 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=420639\">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=P%281%2Br%2Fn%29%5E%28n%2At%29 ALIGN=MIDDLE  ALT=\"A=P%281%2Br%2Fn%29%5E%28n%2At%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the compound interest formula\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25000=10000%281%2Br%2F2%29%5E%282%2A20%29 ALIGN=MIDDLE  ALT=\"25000=10000%281%2Br%2F2%29%5E%282%2A20%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=25000 ALIGN=MIDDLE  ALT=\"A=25000\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P=10000 ALIGN=MIDDLE  ALT=\"P=10000\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n=2 ALIGN=MIDDLE  ALT=\"n=2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=20 ALIGN=MIDDLE  ALT=\"t=20\"   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=25000=10000%281%2Br%2F2%29%5E%2840%29 ALIGN=MIDDLE  ALT=\"25000=10000%281%2Br%2F2%29%5E%2840%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2 ALIGN=MIDDLE  ALT=\"2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20 ALIGN=MIDDLE  ALT=\"20\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40 ALIGN=MIDDLE  ALT=\"40\"   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=25000%2F10000=%281%2Br%2F2%29%5E%2840%29 ALIGN=MIDDLE  ALT=\"25000%2F10000=%281%2Br%2F2%29%5E%2840%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10000 ALIGN=MIDDLE  ALT=\"10000\"   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=2.5=%281%2Br%2F2%29%5E%2840%29 ALIGN=MIDDLE  ALT=\"2.5=%281%2Br%2F2%29%5E%2840%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Evaluate <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25000%2F10000 ALIGN=MIDDLE  ALT=\"25000%2F10000\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2.5 ALIGN=MIDDLE  ALT=\"2.5\"   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=root%2840%2C2.5%29=1%2Br%2F2 ALIGN=MIDDLE  ALT=\"root%2840%2C2.5%29=1%2Br%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Take the 40th root of both sides.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1.02317165469772=1%2Br%2F2 ALIGN=MIDDLE  ALT=\"1.02317165469772=1%2Br%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Take the 40th root of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2.5 ALIGN=MIDDLE  ALT=\"2.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1.02317165469772 ALIGN=MIDDLE  ALT=\"1.02317165469772\"   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=1.02317165469772-1=r%2F2 ALIGN=MIDDLE  ALT=\"1.02317165469772-1=r%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 1 from both sides.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.0231716546977176=r%2F2 ALIGN=MIDDLE  ALT=\"0.0231716546977176=r%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Combine like terms.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2A0.0231716546977176=r ALIGN=MIDDLE  ALT=\"2%2A0.0231716546977176=r\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply boths sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2 ALIGN=MIDDLE  ALT=\"2\"   DISABLED_style= \"max-width:90%; height:auto;\" > to isolate \"r\".\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.0463433093954353=r ALIGN=MIDDLE  ALT=\"0.0463433093954353=r\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2 ALIGN=MIDDLE  ALT=\"2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.0231716546977176 ALIGN=MIDDLE  ALT=\"0.0231716546977176\"   DISABLED_style= \"max-width:90%; height:auto;\" > to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.0463433093954353 ALIGN=MIDDLE  ALT=\"0.0463433093954353\"   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=r=0.0463433093954353 ALIGN=MIDDLE  ALT=\"r=0.0463433093954353\"   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=r=0.0463 ALIGN=MIDDLE  ALT=\"r=0.0463\"   DISABLED_style= \"max-width:90%; height:auto;\" > Round to the nearest ten-thousandth.\r<BR>\n" );
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document.write( "So the interest rate is 4.63% (multiply by 100 to convert to a percentage)<BR>\n" );
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