document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=378491>Question 378491</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If 7000 is placed into an account with an annual rate of 4.5%, how long will it take to quadruple if interest is compounded annually? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #268869 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=268869\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use the formula <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=B+=+P%281%2Br%2Fn%29%5E%28nt%29 ALIGN=MIDDLE  ALT=\"B+=+P%281%2Br%2Fn%29%5E%28nt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Now n = 1, r = 0.045, P = 7000.  we want\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=28000+=+7000%281%2B0.045%29%5Et ALIGN=MIDDLE  ALT=\"28000+=+7000%281%2B0.045%29%5Et\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4+=+1.045%5Et ALIGN=MIDDLE  ALT=\"4+=+1.045%5Et\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Then ln4 = t*ln1.045, or t = ln4/ln1.045 = 31.49 years. </SPAN>\n" );
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