Probability of getting a sum which is a multiple of 3 when two fair dice are thrown
The sum of the numbers obtained when two dice are thrown can range from 2 to 12. To find the probability of getting a sum which is a multiple of 3, we need to first identify the possible outcomes that fulfill this condition.

Possible outcomes for getting a sum which is a multiple of 3
- The sums which are multiples of 3 are 3, 6, 9, and 12.
- To get a sum of 3, the possible outcomes are (1, 2) and (2, 1).
- To get a sum of 6, the possible outcomes are (1, 5), (2, 4), (3, 3), (4, 2), and (5, 1).
- To get a sum of 9, the possible outcomes are (3, 6), (4, 5), and (5, 4).
- To get a sum of 12, the only possible outcome is (6, 6).

Total possible outcomes
- There are a total of 6 x 6 = 36 possible outcomes when two dice are thrown.

Favorable outcomes
- There are 2 + 5 + 3 + 1 = 11 favorable outcomes for getting a sum which is a multiple of 3.

Calculating the probability
- Probability = Number of favorable outcomes / Total possible outcomes
- Probability = 11 / 36 ≈ 0.3056 or 30.56%
Therefore, the probability of getting a sum which is a multiple of 3 when two fair dice are thrown is approximately 30.56%.