document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1202122>Question 1202122</A>: <I><SPAN STYLE=\"word-break: break-all;\"> On a string of pearls, the largest pearl is in the center and the smallest pearls are on the <BR>\n" );
document.write( "ends. Each of the small pearls on the two ends costs $1; each of the next larger pearls costs <BR>\n" );
document.write( "$2 each; the third pearl from each end costs $3 each; and so on. On the basis of this plan, <BR>\n" );
document.write( "how much would a string of 9 pearls cost? 12? 25? n? what equation can be used to find the cost of any number of pearls? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #836764 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=836764\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1,2,3,4,5,4,3,2,1<BR>\n" );
document.write( "Since the number of pearlsare small it is easy to sum the cost for the string. 25\r<BR>\n" );
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document.write( "There are twosequences\r<BR>\n" );
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document.write( "1to 5 increasing by 1\r<BR>\n" );
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document.write( "6to 9 decreasing by 1\r<BR>\n" );
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document.write( "Sn = n/2 (a+l) ( arithmetic  sequence) Sum of n terms<BR>\n" );
document.write( "a=1 l=5 n=5\r<BR>\n" );
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document.write( "5/2(1+5) =15\r<BR>\n" );
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document.write( "Now the other part\r<BR>\n" );
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document.write( "4/2(4+1)= 10\r<BR>\n" );
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document.write( "10+15=25 </SPAN>\n" );
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