document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=985294>Question 985294</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is [math]17+18+19+\cdots+42+43[/math] ?<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 #606118 by </B><A HREF=/tutors/aboutme.mpl?userid=swincher4391><B>swincher4391(1107)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=swincher4391><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=swincher4391><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=606118\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The main formula we are going to use here is called the Closed Form. \r<BR>\n" );
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document.write( "The sum from 1 to n is n(n+1)/2.\r<BR>\n" );
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document.write( "So Let's take the sum from 1 to 43 first.  That would be 43(44)/2 = 946.\r<BR>\n" );
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document.write( "Notice that in order to get the sum from 17 to 43, we need to subtract off 1 through 16.\r<BR>\n" );
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document.write( "So the sum from 1 to 16 is  16(17)/2 = 136\r<BR>\n" );
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document.write( "So 946 - 136 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28810%29 ALIGN=MIDDLE  ALT=\"highlight%28810%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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