Puzzle always equals 1089
by William Behringer
(Opelousas, Louisiana USA)
As one who is not and never has been "good" in math there is a question that has ever puzzled me and I have never found anyone who can explain it. Here's hoping that you can explain it in a way I can "get".
Why can one take any three numbers from 1 to 9, ie 357 825 or 912, reverse there sequence, ie 357 would become753. Then subtract the smaller from the larger. When that answer is obtained, reverse that number and add ie 753 minus 357 = 396. Reverse 396 ie 693 and add will always equal 1089. This is true regardless of what the starting numbers were. I can't for the life of me understand this. How can this process result in the same answer "1089" whether you start with 123 or 987? Please explain this to me.