document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=896969>Question 896969</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine the number of terms in the arithmetic series where a1=19, an=89 and Sn= 810<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 #543898 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=543898\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a1=19, an=89 and Sn= 810<BR>\n" );
document.write( "S = ½(a1 + an)n<BR>\n" );
document.write( "810 = ½(19 + 89)n<BR>\n" );
document.write( "810 = ½(108)n<BR>\n" );
document.write( "810 = 54n<BR>\n" );
document.write( "n=15<BR>\n" );
document.write( "89 = 19 + (14)d<BR>\n" );
document.write( "70=14d<BR>\n" );
document.write( "d=5<BR>\n" );
document.write( "19,24,29,34,39,<BR>\n" );
document.write( "44,49,54,59,64,<BR>\n" );
document.write( "69,74,79,84,89<BR>\n" );
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