document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1160228>Question 1160228</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find S20 for the arithmetic series 24+16+8 + … . </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #783472 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=783472\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> sum is (n/2)(2a+d(n-1))<BR>\n" );
document.write( "a1=24<BR>\n" );
document.write( "a2=24-8, and d=8, n=20<BR>\n" );
document.write( "a3=24-(8*2)=8\r<BR>\n" );
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document.write( "a20=24-(8*19)=-128<BR>\n" );
document.write( "sum is (10)(48+(-8)(19))=10 (-104)=-1040\r<BR>\n" );
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document.write( "check<BR>\n" );
document.write( "sum <BR>\n" );
document.write( "24/16/8/0/-8/-16/...../-128 </SPAN>\n" );
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