document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=390411>Question 390411</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The first 15 letters of the following pattern are given.  If this pattern were to be continued, what would the 100th letter?\r<BR>\n" );
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document.write( "A B B C C C D D D D E E E E E ... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #276849 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=276849\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Instead of listing all 100 letters, we can notice that there is 1 A, 2 B's, 3 C's, 4 D's, etc.\r<BR>\n" );
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document.write( "Note that 1+2+...+13 = 91 and 1+2+...+14 = 105. Since M and N are the 13th and 14th letters of the alphabet, we can say that there are 91 letters in the subsequence\r<BR>\n" );
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document.write( "A B B ...M M M (all M's included)\r<BR>\n" );
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document.write( "and 105 terms in\r<BR>\n" );
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document.write( "A B B ...N N N (all N's included)\r<BR>\n" );
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document.write( "This implies that the 92nd through 105th terms are all N, so the 100th term is N. </SPAN>\n" );
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