document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=656795>Question 656795</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find Sn fort he given arithmetic series.. a1=22 d=-8 n=21<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 #409650 by </B><A HREF=/tutors/aboutme.mpl?userid=jhadipak><B>jhadipak(3)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jhadipak><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=409650\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solution: we know that Sn = (n/2)(2a + (n - 1)d)<BR>\n" );
document.write( "where n = last term<BR>\n" );
document.write( "a = first term and d = difference between two terms.<BR>\n" );
document.write( "Datas We have given in the problem as a1=22 d=-8 n=21<BR>\n" );
document.write( "where a1 = 1st term<BR>\n" );
document.write( "plugging all the given values will result<BR>\n" );
document.write( "Sn = (n/2)(2a + (n - 1)d)<BR>\n" );
document.write( "   = (21/2)(2(22) + (21 - 1)(-8))<BR>\n" );
document.write( "   = (21/2)(44 + (20)(-8))<BR>\n" );
document.write( "   = (21/2)(44 - 160)<BR>\n" );
document.write( "   = (21/2)(-116)<BR>\n" );
document.write( "   = 21(-58)<BR>\n" );
document.write( "   = -1218<BR>\n" );
document.write( "As we can see that the difference of the number given is negative so the last term must be negative.<BR>\n" );
document.write( "Hope this will help you!! </SPAN>\n" );
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