document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=85114>Question 85114</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many seven-digit phone numbers can be formed if the first digit cannot be 0 and \r<BR>\n" );
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document.write( "a)repetition of digits is not permitted?\r<BR>\n" );
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document.write( "b)if repetition of digits is permitted?<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 #61332 by </B><A HREF=/tutors/aboutme.mpl?userid=Nate><B>Nate(3500)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Nate><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=61332\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How many seven-digit phone numbers can be formed if the first digit cannot be 0 and <BR>\n" );
document.write( "_ _ _ _ _ _ _ ... To complete this .. you must know how many numbers CAN be used ...<BR>\n" );
document.write( "a)repetition of digits is not permitted? <BR>\n" );
document.write( "First Digit can not be 0 and another nummer -> 8<BR>\n" );
document.write( "Second Digit can not be the chosen number -> 9<BR>\n" );
document.write( "8 * 9 * 8 * 7 * 6 * 5 * 4<BR>\n" );
document.write( "483,840<BR>\n" );
document.write( "b)if repetition of digits is permitted?<BR>\n" );
document.write( "8 * 10 * 10 * 10 * 10 * 10 * 10<BR>\n" );
document.write( "8,000,000 </SPAN>\n" );
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