Explanation:
the probabilty to roll a specific number between 1 and 6 is 1/6 per die.
when we have the combination of 2 independent events (the outcome of the first does not impact the outcome of the second), we multiply the 2 individual probabilities for the combined probability.
9.
to get 12 as the sum of 2 rolled dice means that both rolls show exactly 6.
the probabilty is therefore
1/6 × 1/6 = 1/36 = 0.027777777...
10.
we have 36 totally possible events (6×6).
the desired ones are the ones with sum 8.
these are the combinations
2 6
3 5
4 4
5 3
6 2
5 cases.
so, the probability is
5/36 = 0.138888888...