Final answer:
The probability of rolling a sum of 6 on a standard pair of six-sided dice is 5 out of 36 or approximately 0.139 when expressed as a decimal.
Step-by-step explanation:
To find the probability of rolling a sum of 6 on a standard pair of six-sided dice, we must first consider all the possible ways two dice can sum to 6. The pairs that sum to 6 are (1,5), (2,4), (3,3), (4,2), and (5,1). That means there are 5 favorable outcomes. Since each die has 6 faces, there are 6 x 6 = 36 possible outcomes when rolling two dice.
Next, we calculate the probability by dividing the number of favorable outcomes by the total number of possible outcomes. So the probability P of rolling a sum of 6 is given by:
P = Number of favorable outcomes / Total number of possible outcomes
P = 5 / 36
As a decimal number rounded to three decimal places, this probability is approximately 0.139.