document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=388118>Question 388118</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a3*a8=300 Sn=128 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #274900 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=274900\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> What kind of sequence is this? (Arithmetic, geometric, harmonic, ...?)\r<BR>\n" );
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document.write( "From the given (a+2d)(a+7d) = 300.  From the second info, we get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28n%2F2%29%282a%2B+%28n-1%29d%29+=+128 ALIGN=MIDDLE  ALT=\"%28n%2F2%29%282a%2B+%28n-1%29d%29+=+128\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Three variables, two equations.  Hmm. Since you chose not to give the value of n, I think you know the solution to the problem yourself.  So I don't need to continue any further. </SPAN>\n" );
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