document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1109416>Question 1109416</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of a finite geometric series. \r<BR>\n" );
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document.write( "Given n=6\r<BR>\n" );
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document.write( "-5, -15, -45, ...,\r<BR>\n" );
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document.write( "I worked this out and ended up with -1820 , but I am not sure the result is correct.\r<BR>\n" );
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document.write( "a1(1&#8722;r^n)/1&#8722;r\r<BR>\n" );
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document.write( "-5(1-3^6/1-2 = 3640/-2 = -1820\r<BR>\n" );
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document.write( "Please let me know if the formula I used was incorrect, thanks!<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #724406 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=724406\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Can check the result<BR>\n" );
document.write( "-5-15-45-135-405-1215=-1820<BR>\n" );
document.write( "you are correct, except the denominator is 1-3 to get -2, not 1-2. </SPAN>\n" );
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