Two different digits from 1 to 9 are chosen randomly to form a 2-digit number. By reversing the order of
the digits, a second 2-digit number is formed. What is the probability that the sum of these two numbers will
be a multiple of the sum of the digits?
What have you tried?
I like this question, it is much easier than it looks
Let the first digit be x and the second by y
You might find it a little easier to think of two different scenarios. Though really this is not necessary.
1. x+y <10
2. x+y >10
If you want to look in advance then just draw up a 9 by 9 grid, fill in the outcomes and see what happens.
Please let 'thedude...' work it out for himself from here.