document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1087136>Question 1087136</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In what time will rupees 1000 becomes Rs. 1331 at 10% rate  p.a compound interest. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #701415 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=701415\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f = p * (1 + r) ^ n\r<BR>\n" );
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document.write( "f is the future value<BR>\n" );
document.write( "p is the present value<BR>\n" );
document.write( "r is the interest rate per time period<BR>\n" );
document.write( "n is the number of time periods.\r<BR>\n" );
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document.write( "in your problem:\r<BR>\n" );
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document.write( "f = 1331<BR>\n" );
document.write( "p = 1000<BR>\n" );
document.write( "r = .1 per year<BR>\n" );
document.write( "n = number of years\r<BR>\n" );
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document.write( "the formula becomes:\r<BR>\n" );
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document.write( "1331 = 1000 * (1 + .1) ^ n\r<BR>\n" );
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document.write( "divide both sides of the equation by 1000 and simplify to get:\r<BR>\n" );
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document.write( "1.331 = 1.1 ^ n\r<BR>\n" );
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document.write( "take the log of both sides of the equation to get:\r<BR>\n" );
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document.write( "log(1.331) = log(1.1 ^ n)\r<BR>\n" );
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document.write( "simplify to get log(1.331) = n * log(1.1)\r<BR>\n" );
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document.write( "solve for n to get n = log(1.331) / log(1.1) = 3\r<BR>\n" );
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document.write( "1000 rupees will become 1331 rupees in 3 years at an interest rate of 10% compounded annually.\r<BR>\n" );
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document.write( "in general, log(b^n) = n*log(b)\r<BR>\n" );
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document.write( "that's one of the basic properties of logarithms.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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