document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1084676>Question 1084676</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the 7th term of an AP is 19 and the 8th term is 22.find the sum of the first 40th terms of the series </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #698760 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=698760\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> an=a1+(n-1)d<BR>\n" );
document.write( "d=3, between 7th and 8th term<BR>\n" );
document.write( "a7=a1+(n-1)d<BR>\n" );
document.write( "a7=a1+6*3=a1+18<BR>\n" );
document.write( "19=a1+18<BR>\n" );
document.write( "a1=1<BR>\n" );
document.write( "a40=1+(39)*3=118<BR>\n" );
document.write( "sum=(40/2)(a1+a40)=20+(1+118)=119*20=2380 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );