Yes, for this problem it doesn't help.. but in general there are problems which ask you to flip the digits and find the possible sums.
For ex. if the digits of a two digit number are flipped and the two numbers added, which of the following is a possible sum..
So K= 10x+y, K'=10y+x,
K+K' = 11(x+y)...
Sum has to be a multiple of 11,
Same way with difference .. K-K' = 9(x-y)
If (x+y) or (x-y) is given you can find the difference or sum.
Again, you might already know this.
Thanks for the tip. But in this case how do you utilize the 10x+y thingie?