document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=880064>Question 880064</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use summation notation to express the sum.\r<BR>\n" );
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document.write( "5+20+80+......+20,971,520  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #531830 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=531830\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Tn = t * r^(n - 1)<BR>\n" );
document.write( "20,971,520  = 5 * 4^(n - 1)<BR>\n" );
document.write( "20,971,520  = 5 * 4^(n - 1)<BR>\n" );
document.write( "4194304=4^(n - 1)<BR>\n" );
document.write( "n=12<BR>\n" );
document.write( "S=t*(1 - r^n)/(1 - r)<BR>\n" );
document.write( "S=5*(1 - 4^12)/(1 - 4)<BR>\n" );
document.write( "S = 27962025 </SPAN>\n" );
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