document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=104065>Question 104065</A>: <I><SPAN STYLE=\"word-break: break-all;\"> {1}find the sum of this geometric progression series 16+1\4+___as far as the 6th term????????{2}find the sum of this arithmetic progression 13.9+___+{-0.5}+{-2.1}+{-3.7} </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #75730 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=75730\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> {1}find the sum of this geometric progression series 16+1\4+___as far as the 6th term????????{2}<BR>\n" );
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document.write( "a(1)=16<BR>\n" );
document.write( "d= (1/4)-16 = (-63/4)<BR>\n" );
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document.write( "So a(6)= a(1)+5d<BR>\n" );
document.write( "a(6) = 16 +5(-63/4) = -62.75<BR>\n" );
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document.write( "Then S(6) = (6/2)(a(1)+a(6))<BR>\n" );
document.write( "S(6) = 3(16-62.75)= -140.25<BR>\n" );
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document.write( "find the sum of this arithmetic progression 13.9+___+{-0.5}+{-2.1}+{-3.7}<BR>\n" );
document.write( "a(1)=13.9<BR>\n" );
document.write( "d=-1.6<BR>\n" );
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document.write( "Determine the order of -3.7<BR>\n" );
document.write( "a(n)=13.9+(n-1)(-1.6)<BR>\n" );
document.write( "-3.7=13.9-1.6n+1.6<BR>\n" );
document.write( "n=12<BR>\n" );
document.write( "so -3.7 is the 12th term of the series.<BR>\n" );
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document.write( "Add the 1st 12 terms:<BR>\n" );
document.write( "S(12)=(12/2)(13.9-3.7)<BR>\n" );
document.write( "S(12)=6(10.2)<BR>\n" );
document.write( "S(12) = 61.2<BR>\n" );
document.write( "================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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