document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=475683>Question 475683</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a theater has 36 rows with 21 seats in the first row, 24 in the second row, 27 in the tird row ans so forth.  hOw many seats are in the theater? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #326177 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=326177\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Sum of an arithmetic sequence is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5Bn%5D+=+%28n%2F2%29%282a%5B1%5D+%2B+%28n-1%29d%29 ALIGN=MIDDLE  ALT=\"S%5Bn%5D+=+%28n%2F2%29%282a%5B1%5D+%2B+%28n-1%29d%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Here, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5B1%5D+=+21 ALIGN=MIDDLE  ALT=\"a%5B1%5D+=+21\"   DISABLED_style= \"max-width:90%; height:auto;\" >, n = 36, and d = 3.\r<BR>\n" );
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document.write( "==> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5B36%5D+=+%2836%2F2%29%282%2A21+%2B+35%2A3%29+=+18%2A147+=+2646 ALIGN=MIDDLE  ALT=\"S%5B36%5D+=+%2836%2F2%29%282%2A21+%2B+35%2A3%29+=+18%2A147+=+2646\"   DISABLED_style= \"max-width:90%; height:auto;\" > seats. </SPAN>\n" );
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