document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=299498>Question 299498</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many three-digit numbers can be formed under the following conditions?<BR>\n" );
document.write( "      (a) The leading digit cannot be zero<BR>\n" );
document.write( "      (b) the leading digit cannot be zero and no repetition of digits<BR>\n" );
document.write( "      (c) the leading digit cannot be zero and the number must be a multiple of 5<BR>\n" );
document.write( "      (d) the number is at least 400\r<BR>\n" );
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document.write( "for (a) i tried doing 9^3 which gives me 729, the ans. in the back of the book says 900, i also tried doing  9 nCr 3 which gave me 85, and 9!/3! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #215186 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley77><B>checkley77(12844)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley77><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=215186\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">       (a) The leading digit cannot be zero<BR>\n" );
document.write( "          The first digit is 1 of 8 the next 2 are 1 of 10.<BR>\n" );
document.write( "          9*10*10=900 ans.\r<BR>\n" );
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document.write( "      (b) the leading digit cannot be zero and no repetition of digits<BR>\n" );
document.write( "          9*9*8=648 ans.\r<BR>\n" );
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document.write( "      (c) the leading digit cannot be zero and the number must be a multiple of 5 <BR>\n" );
document.write( "          9*8*1=72 ans.<BR>\n" );
document.write( "      (d) the number is at least 400<BR>\n" );
document.write( "          1*9*8=72 ans. <BR>\n" );
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