The probability of rolling a sum of 3 on a standard pair of six-sided dice:
First we find total of possible combinations on a standard pair of six-sided dice. Since there are six sides on each die, numbered 1 through 6, we see that there are 6 times 6 = 36 combinations (if this is unclear, please note that taking one number at a time on the first die, that it may combine with each of the possible numbers on the second die... doing this for each of the six numbers on the first die and combining with each of the numbers on the second die, we have 6X6 = 36).
Now, of the 36 combinations, how many of those combinations sum to 3? Notice that 1 + 2 = 3 (1 from the first die and 2 from the second) or 2 + 1 = 3 (two from the first die and 2 from the second die). There are no other combinations that sum to 3, so we have 2 out of a total of 36 combinations that sum to 3.
Therefore, the answer is 2/36 = 1/18. So, 1/18 is your final answer is fractional form, and in decimal form we have 1/18 = 0.0555555555555555555forever... = 0.0556 rounded to four decimals.
Final answer in fractional form: 1/18 Final answer in decimal form rounded to four decimals: 0.0556
