document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=993938>Question 993938</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Cody built a pyramid of Lego.  He rectangular Lego that were four bumps by two bumps.  He started with one Lego in the top level.  Underneath that he put in as many Lego as needed to leave one row of bumps all the way around the outside on each level.  He was able to make ten layers on his pyramid before he ran out of Lego.  The inside of the pyramid is completely filled in with Lego, many which are not visible to someone looking at the top of the pyramid.  <BR>\n" );
document.write( "a.  How many Lego are in the Pyramid?<BR>\n" );
document.write( "b.  How many bumps total on all levels are visible on the outside of the pyramid?<BR>\n" );
document.write( "c.  If Cody had an infinite supply of Lego, how many total bumps on all levels would be visible in a pyramid with \"n\" layers of Lego? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #613151 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=613151\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "Re: part c.\r<BR>\n" );
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document.write( "The number of exposed bumps on the nth level is 8n.  Hence the total number of exposed bumps on an <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large n\">-level pyramid is:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ 8\sum_{k=1}^n\, k\">\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \ \\r\"> </SPAN>\n" );
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