document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=970618>Question 970618</A>: <I><SPAN STYLE=\"word-break: break-all;\"> an arithmetic sequence formed of 11 terms ,its middle term equals 20. find the sum of it's terms ,and find a sequence which verifies the equation.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #593314 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=593314\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can pick any common difference you want.  To be simple, you can pick d=1.  The terms will extend to 20+5*1 and to 20-5*1; which are 25 and 15.  The general terms would be   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15%2B1%2A%28n-1%29 ALIGN=MIDDLE  ALT=\"15%2B1%2A%28n-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "First term is 15 for when n=1.<BR>\n" );
document.write( "You can either derive or look-up the formula for SUM of an arithmetic sequence. </SPAN>\n" );
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