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a question about permutation in the digits in the decimal system
I dont get how it works but the method is:
think of a three didgit number with none of the same didgits ; 124 Reverse it ; 421 then take the smallest from the biggest ; 421-124=297 Then reverse your answer ; 792 Then add them together ; 792+297=1089
Now remember that number then do it again with a different number
867 768 867-768=099 990 990+99=1089
I dont get how it works
can you find a number that doesn't ???