document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=41932>Question 41932</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find S(n) for the arithmetic series in which a(1)=-11, a(n)=13, and n=7.\r<BR>\n" );
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document.write( "Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #27075 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=27075\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The formula for the sum of an arithmetic series is<BR>\n" );
document.write( "S = (n/2)(a(1) + a(n))<BR>\n" );
document.write( "S = (7/2)(-11 + 13)<BR>\n" );
document.write( "S = (7/2)(2)<BR>\n" );
document.write( "S = 7 </SPAN>\n" );
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