document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1001359>Question 1001359</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A campus telephone extension has four digits. If the first digit cannot be 0, how many different extensions exist? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #618573 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52797)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=618573\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "There are 9 options for the first digit (1, 2, 3, 4, 5, 6, 7, 8, 9);\r<BR>\n" );
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document.write( "10 options for the second digit;\r<BR>\n" );
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document.write( "10 for the third, and \r<BR>\n" );
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document.write( "10 for the fourth digit.\r<BR>\n" );
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document.write( "In total, there are 9*10*10*10 = 9000 options for 4-digit extension.\r<BR>\n" );
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