document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=3864>Question 3864</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If the two-digit integers M and N are positive and have the same digits, but in reverse order, which of the following CANNOT be the sum of M and N ?<BR>\n" );
document.write( "   (A) 181<BR>\n" );
document.write( "   (B) 163<BR>\n" );
document.write( "   (C) 121<BR>\n" );
document.write( "   (D) 99<BR>\n" );
document.write( "   (E) 44<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 #1693 by </B><A HREF=/tutors/aboutme.mpl?userid=khwang><B>khwang(438)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=khwang><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=1693\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Let M = 10a + b, then N = 10 b+ a,\r<BR>\n" );
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document.write( " So M + N = 11 a + 11 b = 11 (a+b) , this means<BR>\n" );
document.write( " M + N should be a multiple of 11.<BR>\n" );
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document.write( " Note amont these 5 integers <BR>\n" );
document.write( " (A) 181   (B) 163<BR>\n" );
document.write( "  are not multiple of 11.\r<BR>\n" );
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document.write( " Hope you can see by direct view without any calculations.\r<BR>\n" );
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document.write( " In fact an ineger is a multiple of 11 if and only if the<BR>\n" );
document.write( " difference of the sum of odd digits and the sum even digits is a multiple <BR>\n" );
document.write( " of 11 . e.g. 286, 8294,73524.\r<BR>\n" );
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document.write( " Kenny </SPAN>\n" );
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