document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=868846>Question 868846</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find out how many years it takes $1800 to double at 3.2% interest compounded weekly.\r<BR>\n" );
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document.write( "Use equation: A=P(1+r/n)^nt\r<BR>\n" );
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document.write( "Show all steps.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #523862 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</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=523862\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You want the formula this way:  A=P(1+r/n)^(nt)<BR>\n" );
document.write( "and as rendered, is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=P%281%2Br%2Fn%29%5E%28nt%29 ALIGN=MIDDLE  ALT=\"A=P%281%2Br%2Fn%29%5E%28nt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "n is the number of compounding for a year.<BR>\n" );
document.write( "t is time in years.<BR>\n" );
document.write( "r is the interest rate as a decimal number.<BR>\n" );
document.write( "P is \"principle\", starting amount.\r<BR>\n" );
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document.write( "You want to find t for n=52, P=1800, and r=0.032.  A=2*P=3600.<BR>\n" );
document.write( "Whether Natural log or Common log is your choice.  You <i>SHOULD</i> solve for t <b>symbolically, first</b>; and then substitute the values.\r<BR>\n" );
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document.write( "My choice is log base 10.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28%28A%29%29=log%28%28P%29%29%2Blog%28%28%281%2Br%2Fn%29%5E%28nt%29%29%29 ALIGN=MIDDLE  ALT=\"log%28%28A%29%29=log%28%28P%29%29%2Blog%28%28%281%2Br%2Fn%29%5E%28nt%29%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%28A%29%29=log%28%28P%29%29%2Bnt%2Alog%28%281%2Br%2Fn%29%29 ALIGN=MIDDLE  ALT=\"log%28%28A%29%29=log%28%28P%29%29%2Bnt%2Alog%28%281%2Br%2Fn%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=nt%2Alog%28%281%2Br%2Fn%29%29=log%28%28A%29%29-log%28%28P%29%29 ALIGN=MIDDLE  ALT=\"nt%2Alog%28%281%2Br%2Fn%29%29=log%28%28A%29%29-log%28%28P%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=nt%2Alog%28%281%2Br%2Fn%29%29=log%28%28A%2FP%29%29 ALIGN=MIDDLE  ALT=\"nt%2Alog%28%281%2Br%2Fn%29%29=log%28%28A%2FP%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and you know that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2FP ALIGN=MIDDLE  ALT=\"A%2FP\"   DISABLED_style= \"max-width:90%; height:auto;\" > will be 2, so make that change now.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=nt%2Alog%28%281%2Br%2Fn%29%29=log%28%282%29%29 ALIGN=MIDDLE  ALT=\"nt%2Alog%28%281%2Br%2Fn%29%29=log%28%282%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=t=%281%2Fn%29%281%2Flog%28%281%2Br%2Fn%29%29%29log%28%282%29%29 ALIGN=MIDDLE  ALT=\"t=%281%2Fn%29%281%2Flog%28%281%2Br%2Fn%29%29%29log%28%282%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=highlight%28t=%281%2Fn%28log%28%281%2Br%2Fn%29%29%29%29log%28%282%29%29%29 ALIGN=MIDDLE  ALT=\"highlight%28t=%281%2Fn%28log%28%281%2Br%2Fn%29%29%29%29log%28%282%29%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >-----<i>these steps and result can look much better on paper or display wall.</i>\r<BR>\n" );
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document.write( "Now substitute the values.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=%281%2F52log%28%281%2B0.032%2F52%29%29%29%2Alog%28%282%29%29 ALIGN=MIDDLE  ALT=\"t=%281%2F52log%28%281%2B0.032%2F52%29%29%29%2Alog%28%282%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "should be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=21%262%2F3 ALIGN=MIDDLE  ALT=\"21%262%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > year or 21 years 8 months </SPAN>\n" );
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