document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=79546>Question 79546</A>: <I><SPAN STYLE=\"word-break: break-all;\"> i need to find the sum of the first nth terms of the arithmetric series.<BR>\n" );
document.write( " 3+8+13+18+23<BR>\n" );
document.write( " n=20   \r<BR>\n" );
document.write( "\n" );
document.write( "Sn=366 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #57086 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=57086\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i need to find the sum of the first nth terms of the arithmetric series.<BR>\n" );
document.write( "3+8+13+18+23<BR>\n" );
document.write( "n=20 <BR>\n" );
document.write( "Sn=366<BR>\n" );
document.write( "---------<BR>\n" );
document.write( "It is a arithmetic sequence with a(1)=3 and d=5<BR>\n" );
document.write( "The 20th terms is a(20)=3+19*5=98<BR>\n" );
document.write( "The sum of the 1st 20 terms is (20/2)(3+98)=1010<BR>\n" );
document.write( "--------<BR>\n" );
document.write( "FYI: Noice the the sum of the 20 terms is the average of <BR>\n" );
document.write( "the 1st an last terms times 20 as you can see here:<BR>\n" );
document.write( "20[(3+98)/2]<BR>\n" );
document.write( "=========<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );