There are 48 possible outcomes in this situation, and of those outcomes, the ones whose sums are a multiple of three are; 12, 21, 15, 51, 24, 42, 33, 18, 27, 36, 63, 45, 54, 48, 57, and 66. So, that is 16 out of 48 possibilities, or 16/48, which simplifies to 1/3. Written as a percent, the probability of getting numbers whose sum is a multiple of three is 33.33%.
