document.write( "Question 283257: Suppose a contest offers $1000 to the person who can guess the winning four digit number. How many possibilities are there? \n" ); document.write( "

Algebra.Com's Answer #205617 by Edwin McCravy(20086) $\"\"$ $\"About$

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Suppose a contest offers $1000 to the person who can guess the winning four digit number. How many possibilities are there?
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document.write( "There are two methods:\r\n" );
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document.write( "Method 1.\r\n" );
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document.write( "There are 9999 integers from 1 to 9999, inclusive.\r\n" );
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document.write( "There are 999 integers from 1 to 999, inclusive,\r\n" );
document.write( "which are not four-digit numbers.\r\n" );
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document.write( "Subtracting:  9999 - 999 = 9000 \r\n" );
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document.write( "Method 2.\r\n" );
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document.write( "There are 9 choices for the first digit (We cannot choose 0)\r\n" );
document.write( "There are 10 choices for the second digit. (We CAN choose 0)\r\n" );
document.write( "There are 10 choices for the third digit. (We CAN choose 0)\r\n" );
document.write( "There are 10 choices for the fourth digit. (We CAN choose 0)\r\n" );
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document.write( "That's 9*10*10*10 = 9000.\r\n" );
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document.write( "Either way, you get 9000.\r\n" );
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document.write( "So he has one chance in 9000 to choose the right one.\r\n" );
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document.write( "Edwin

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