Question 1138063
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The difference between the 2-digit number AB and the2-digit number BA is 9 times the difference between the two digits A and B.<br>
Since in this problem the difference between AB and BA is 36, the difference between A and B is 4.<br>
Then with the difference between A and B being 4 and their sum being 10, it is easy to see the the two digits are 7 and 3.<br>
Then you just need to read the problem to see that the number with the digits reversed is smaller; so the original number is 73.