document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=304514>Question 304514</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose n>1. An n-digit number is a list of n digits where the first digit in the list is NOT zero.\r<BR>\n" );
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document.write( "a) How many n-digit number are there?<BR>\n" );
document.write( "b) How many n-digit numbers contain no zeroes?\r<BR>\n" );
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document.write( "c) How many n-digit numbers contain at least one zero<BR>\n" );
document.write( "hint: Use a) and b) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #218135 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=218135\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Suppose n>1. An n-digit number is a list of n digits where the first digit in the list is NOT zero. <BR>\n" );
document.write( "a) How many n-digit number are there?<BR>\n" );
document.write( "Ans: 9*10^(n-1)<BR>\n" );
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document.write( "b) How many n-digit numbers contain no zeroes?<BR>\n" );
document.write( "Ans: 9^(n)<BR>\n" );
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document.write( "c) How many n-digit numbers contain at least one zero<BR>\n" );
document.write( "hint: Use a) and b)<BR>\n" );
document.write( "Ans: 9*10^(n-10 - 9^(n)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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