document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1178646>Question 1178646</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A four-digit number abcd is called cool if a is divisible by 4, the two-digit number ab is divisible by 5, the three-digit number abc is divisible by 6 and abcd is divisible by 7. How many cool numbers are there where 8 is not one of the digits? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #808040 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=808040\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
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document.write( "There is no fancy mathematics involved in solving this problem.  Do it yourself.<br><BR>\n" );
document.write( "(1) a is divisible by 4.  What are the possible values of a?<BR>\n" );
document.write( "(2) ab is divisible by 5, so a is either 0 or 5.  From (1) and (2), what are the possibilities for the string ab?<BR>\n" );
document.write( "(3) abc is divisible by 6.  For each of the possible strings ab, what digit(s) c make abc divisible by 6?<BR>\n" );
document.write( "(4) For the possible strings abc from steps (1) to (3), what digit(s) make abcd divisible by 7?<br><BR>\n" );
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