Find a four-digit number with four different digits, that is equal to the number formed by its digits in descending order minus the number formed by its digits in ascending order.

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Take any four consecutive digits. Subtract the ascending number from the descending one, and the answer will be 3087. Repeat the subtraction process (descending minus ascending) with these digits and the answer is 8352. Repeat the process a third time with these digits, and the answer is 6174

Posted by Bryan on 2003-04-26 17:36:06