document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=856215>Question 856215</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you please help me out with this? This is very difficult for me. I understand that the pattern between the numbers is that you are squaring the number each time, but that only makes it harder for me to solve. I don't know where to begin. Can you please explain how solve this problem? I would REALLY appreciate it!!\r<BR>\n" );
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document.write( "What is the sum of the geometric sequence 4, 16, 64, … if there are 8 terms? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #515808 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=515808\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It has two patterns<BR>\n" );
document.write( "2^2, 4^2, 8^2 which is not geometric<BR>\n" );
document.write( "and<BR>\n" );
document.write( "4, 4*4, 4*16 which is geometric,<BR>\n" );
document.write( "Your ratio (r)  is 4<BR>\n" );
document.write( "t1=4 n=8 r=4\r<BR>\n" );
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document.write( "Tn = t1 * r^(n - 1)\r<BR>\n" );
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document.write( "S=t1*(1 - r^n)/(1 - r)<BR>\n" );
document.write( "S=4*(1 - 4^8)/(1 - 2)<BR>\n" );
document.write( "S = 262140<BR>\n" );
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