sum of the digits of a two digit number is 12. the given number exceeds the number obtained by interchanging the digit by 36. find the given number.

Answer 1

If the number is xy, then

x+y=12
10x+y = 36+10y+x

Now just find x and y.

If that's too hard, just think of the pairs of digits that add to 12, and try them out.