I think it's true cause
rs
Here are the probabilities for getting a sums 2-12. (you can't get 1 as a sum after rolling two die)
2 - 1/36
3 - 2/36 = 1/18
4 - 3/36 = 1/12
5 - 4/36 = 1/9
6 - 5/36
7 - 6/36 = 1/6
8 - 5/36
9 - 4/36 = 1/9
10 - 3/36 = 1/12
11 - 2/36 = 1/18
12 - 1/36
Since composite numbers are 4,6,8,9,10,12. Add up the probabilities for all of those.
21/36=7/12