document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=411231>Question 411231</A>: <I><SPAN STYLE=\"word-break: break-all;\"> in an arithmetic sequence, a1=2 and a40=80.  what is the value of the sum of a2+a4+a6+a8+...a40? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #289093 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=289093\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "To find the sum of a certain number of terms of an arithmetic sequence:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Sn=n%28a1%2Ban%29%2F2 ALIGN=MIDDLE  ALT=\"Sn=n%28a1%2Ban%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "where <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Sn ALIGN=MIDDLE  ALT=\"Sn\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the sum of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n ALIGN=MIDDLE  ALT=\"n\"   DISABLED_style= \"max-width:90%; height:auto;\" > terms (nth partial sum),  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a1 ALIGN=MIDDLE  ALT=\"a1\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the first term,  an is the nth term\r<BR>\n" );
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document.write( "given: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a1=2 ALIGN=MIDDLE  ALT=\"a1=2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a40=80 ALIGN=MIDDLE  ALT=\"a40=80\"   DISABLED_style= \"max-width:90%; height:auto;\" >  \r<BR>\n" );
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document.write( "to find: the sum of a2+a4+a6+a8+...a40\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Sn=n%28a1%2Ban%29%2F2 ALIGN=MIDDLE  ALT=\"Sn=n%28a1%2Ban%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%2840%29=40%282%2B80%29%2F2 ALIGN=MIDDLE  ALT=\"S%2840%29=40%282%2B80%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%2840%29=40%2A82%2F2 ALIGN=MIDDLE  ALT=\"S%2840%29=40%2A82%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%2840%29=40%2A41 ALIGN=MIDDLE  ALT=\"S%2840%29=40%2A41\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%2840%29=1640 ALIGN=MIDDLE  ALT=\"S%2840%29=1640\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
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