document.write( "Question 1024465: Determine how many numbers between 10 and 1000 inclusive
\n" ); document.write( "contain a repeated digit and the rest of the digits(if any)
\n" ); document.write( "are distinct.(eg:101,229).\r
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\n" ); document.write( "For two digits number : [P(9,1)*P(9,1)-1]+[[P(9,1)*P(9,1)]/9]=89.
\n" ); document.write( "For three digits number : [9*9*8]+[9*9]+[9*9]+[9*9]=891.
\n" ); document.write( "891 + 89 = 980 numbers.
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\n" ); document.write( "Thanks in advance \n" ); document.write( "
Algebra.Com's Answer #639996 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "No, that's way too many!  Think of the number of ways\r\n" );
document.write( "there are to choose the digits.  Don't depend on\r\n" );
document.write( "permutation formulas.  Think it through.\r\n" );
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document.write( "Case 1:  2 digit numbers  \r\n" );
document.write( "There are 9 2-digit numbers, 11,22,33,...,99\r\n" );
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document.write( "Case 2:  3 digit numbers \r\n" );
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document.write( "There are three types of these numbers: AAB, ABA, and ABB \r\n" );
document.write( "(For example 773, 505, and 911)\r\n" );
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document.write( "For each of these 3 types,\r\n" );
document.write( "There are 9 choices for the A, 1 through 9 (can't use 0) \r\n" );
document.write( "There are 9 remaining choices for the B, (can use 0)\r\n" );
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document.write( "That's 3*9*9 = 243\r\n" );
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document.write( "Grand total: 9+243 = 252.\r\n" );
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document.write( "Edwin
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