document.write( "Question 540987: A credit card number has 5 digits (between 1 to 9). The first two digits
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Algebra.Com's Answer #354027 by AnlytcPhil(1806)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Since the first two digits are 12 in that order, there is only 1 way\r\n" );
document.write( "to choose the first two digits.  That's 1 way to choose the first\r\n" );
document.write( "two digits.\r\n" );
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document.write( "Since the third digit is bigger than 6, it can only be 7,8, or 9.\r\n" );
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document.write( "So that's 1×3 choices for the the first three digits.\r\n" );
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document.write( "Since the 4th digit is 3 times the 5th digit, the number can only end in \r\n" );
document.write( "31, 62, or 93\r\n" );
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document.write( "So for each of the 1×3 way to choose the first 3 digits, there are 3\r\n" );
document.write( "ways to choose the last two digits.\r\n" );
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document.write( "That's a total of 1×3×3 = 9 possible numbers.  Here are all 9:\r\n" );
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document.write( "1.  12731\r\n" );
document.write( "2.  12762\r\n" );
document.write( "3.  12793\r\n" );
document.write( "4.  12831\r\n" );
document.write( "5.  12862\r\n" );
document.write( "6.  12893\r\n" );
document.write( "7.  12931\r\n" );
document.write( "8.  12962\r\n" );
document.write( "9.  12993\r\n" );
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document.write( "Edwin
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