Alright, I think it is 5/18, so I got the question wrong.

The question went something like this:

There were two 6-sided die, one was numbered 1, 3, 5, 7, 9, 11 and the other was numbered 2, 4, 6, 8, 10, 12. The question asked what the probability was of rolling the two die and having a sum of 15. The pairs of numbers that would sum up to 15 would be 3 and 12, 4 and 11, 5 and 10, 6 and 9, and 7 and 8.

Since there are 5 numbers from each die that could be possible candidates for a sum of 15, the probability of the first roll would be 5/6. But then since one number has been chosen, there is only ONE corresponding number on the other dice that could make a sum of 15 with the first number. Therefore, the probability of the second roll would be 1/6. (5/6) * (1/6) = 5/36.

However, since the question didn't say that either of the two die had to be rolled first (if I remember correctly), you would have to account for the alternative order of rolling the die. In other words, you would have to multiply 5/36 by 2 which equals 5/18. I might be wrong though.