document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1084071>Question 1084071</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given the first four terms and the number of terms in the series, what is the sum of the following arithmetic series?<BR>\n" );
document.write( "20 + 27 + 34 + 41, n = 16 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #698140 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=698140\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Sum is n(a1+an)/2<BR>\n" );
document.write( "a1=20, and an=a1+15*7=125<BR>\n" );
document.write( "therefore, sum is 16(20+125)/2=8*145=1160<BR>\n" );
document.write( "check<BR>\n" );
document.write( "20+27+34+41+48+55+62+69+76+83+90+97+104+111+118+125=1160<BR>\n" );
document.write( " </SPAN>\n" );
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