When rolling two standard die there are 36 possibilities.
The smallest sum being 2 (rolling a 1,1) and the largest being 12 (rolling a (6,6).
Of that range, prime numbers are 2, 3, 5, 7, 11.
In the sums there are 1-2's, 2-3's, 4-5's, 6-7's, and 2-11's.
P(sum 2 is die prime) = 15/36 = 5/12
