document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=846969>Question 846969</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a group of children, each child gives one gift to other. If total numbers of gift are 90, then find the number of children in the group. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #510073 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=510073\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This would be just like the \"hand-shake\" problem.  You would want to be able to make a polygon so that you can show 90 individual connections among all vertices.  Start with a triangle; it has 3 connections.  Next use a square (four sides); it will have 4 connections.  Next, use a pentagon; it has 7 connections.  Continue on this way...\r<BR>\n" );
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document.write( "Look at the wikipedia article, http://en.wikipedia.org/wiki/Handshake_problem<BR>\n" );
document.write( "See the section about Triangular Numbers.  The given 90 gifts in your exercise would most closely correspond to 14 students. </SPAN>\n" );
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