document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=850701>Question 850701</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if seventh term of geometric sequence is 64 and sum of first ten terms is 1023 then find the sum of fifteen terms of gs.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #512905 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=512905\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Tn = t1 * r^(n - 1)<BR>\n" );
document.write( "64 = t * r^(6)\r<BR>\n" );
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document.write( "Sum =t1*(1 - r^n)/(1 - r)<BR>\n" );
document.write( "1023 = t*(1 - r^10)/(1 - r),<BR>\n" );
document.write( "64 = t * r^(6)\r<BR>\n" );
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document.write( "r=2.,   t=1.<BR>\n" );
document.write( "S =1*(1 - 2^15)/(1 - 2)<BR>\n" );
document.write( "S = 32767 </SPAN>\n" );
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