Check the table attached.
The first coordinates of each pair represent the 1.roll, and the second coordinates the 2nd, roll.
All the possible outcomes are {(1, 1), (1, 2).... (6, 5), (6, 6)}, a total of 36, as can be seen in the table.
Each outcome has a chance of 1 out 36 total possible outcomes of occurring.
So the probability is 1/36=0.02778