Question 1026902:  Show that the set of natural numbers whose decimal digits are all even and different is finite. 
 Answer by richard1234(7193)      (Show Source): 
You can  put this solution on YOUR website! There are only five even decimal digits (0,2,4,6,8) and any natural number formed from some of these digits has at most 5 digits. Since there are only a finite number of natural numbers of at most 5 digits, this set is finite. 
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