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Subj:.....Math Prob. - Four Digit Number #2 (S579b) 
          From: Puzzles And Brain Teasers on 2/19/2008 
 Source: http://www.apuzzlezone.com/adailypuzzle/02-19-08.html
 

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

                  THE SOLUTION

                             6174
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