document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=11037>Question 11037</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the correct way to find the sum of 1+4+7+10+13......100 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #5788 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=5788\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> one formula is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5Bn%5D+=+n%2F2%28a%2Bl%29 ALIGN=MIDDLE  ALT=\"S%5Bn%5D+=+n%2F2%28a%2Bl%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > where a is first term and l is last term.\r<BR>\n" );
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document.write( "Issue is, how many terms?, well 3,6,9,...,102 is the 3-times table with 34 terms.\r<BR>\n" );
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document.write( "1,4,7,...,100 is the same set of numbers, shunted down by 2... so 34 terms.\r<BR>\n" );
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document.write( "so, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5B34%5D+=+34%2F2%281%2B100%29 ALIGN=MIDDLE  ALT=\"S%5B34%5D+=+34%2F2%281%2B100%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5B34%5D+=+17%28101%29 ALIGN=MIDDLE  ALT=\"S%5B34%5D+=+17%28101%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5B34%5D+=+1717 ALIGN=MIDDLE  ALT=\"S%5B34%5D+=+1717\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "jon.<BR>\n" );
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