document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=174108>Question 174108</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Your class has just completed a unit on divisibility rules.  One of the students asks why divisibility by numbers other than 3 and 9 can not be tested by dividing the sum of the digits by the tested number.  How do you respond? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #129075 by </B><A HREF=/tutors/aboutme.mpl?userid=bob123132><B>bob123132(33)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bob123132><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=129075\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> No. Because some numbers are factors of 3 AND 5 which would make them be counted twice. Take this for example up to 20:<BR>\n" );
document.write( "3:3,6,9,12,15,18<BR>\n" );
document.write( "5:5,10,15,20<BR>\n" );
document.write( "If you used the students way it would equal 10 different numbers. But if you have noticed, 15 has both so right there, there are only 9 DIFFERENT numbers </SPAN>\n" );
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