document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=773818>Question 773818</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ben wants to double his money in 8 years by investing it in a savings account with interest compounded annually. What interest rate must the savings account offer in order for his money to double in 8 years? (Use the formula a=p(1+i)^n)\r<BR>\n" );
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document.write( "Thanks for any help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #471903 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=471903\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i is assumed in decimal form.  Choose a=2 and p=1.  n=8 as given.<BR>\n" );
document.write( "SOLVE FOR i.  This will involve logarithms.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2=1%2A%281%2Bi%29%5En ALIGN=MIDDLE  ALT=\"2=1%2A%281%2Bi%29%5En\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2=%281%2Bi%29%5E8 ALIGN=MIDDLE  ALT=\"2=%281%2Bi%29%5E8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%282%29=log%28%281%2Bi%29%5E8%29 ALIGN=MIDDLE  ALT=\"log%282%29=log%28%281%2Bi%29%5E8%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%282%29=8%2Alog%28%281%2Bi%29%29 ALIGN=MIDDLE  ALT=\"log%282%29=8%2Alog%28%281%2Bi%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28%281%2Bi%29%29=%281%2F8%29log%282%29 ALIGN=MIDDLE  ALT=\"log%28%281%2Bi%29%29=%281%2F8%29log%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "To continue, decide which base you want.  Euler number, or ten.  Either of them would be practical.  You would want to actually solve for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2Bi%29 ALIGN=MIDDLE  ALT=\"%281%2Bi%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > and then subtract 1 in order to have i.  \r<BR>\n" );
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document.write( "Continuing with base-ten, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%2810%2C%281%2Bi%29%29=0.03763 ALIGN=MIDDLE  ALT=\"log%2810%2C%281%2Bi%29%29=0.03763\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%5E0.03763=1%2Bi ALIGN=MIDDLE  ALT=\"10%5E0.03763=1%2Bi\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%281%2Bi=1.090508%29 ALIGN=MIDDLE  ALT=\"highlight%281%2Bi=1.090508%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28i=0.0905%29 ALIGN=MIDDLE  ALT=\"highlight%28i=0.0905%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > staying with just three significant figures.  This means 9.05% </SPAN>\n" );
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