What is the probability of rolling a sum of 7 with two dice?

• A. 1/6
• B. 1/12
• C. 1/36
• D. 1/3

Answer: (A)

To find the probability of rolling a sum of 7 with two six-sided dice, we first need to determine how many possible combinations of dice rolls can result in that sum. When two dice are rolled, there are a total of 36 possible outcomes (6 faces on the first die multiplied by 6 faces on the second die).

Next, we calculate the combinations that yield a sum of 7:

1. (1, 6)

2. (2, 5)

3. (3, 4)

4. (4, 3)

5. (5, 2)

6. (6, 1)

There are 6 combinations that result in a sum of 7.

To find the probability, we take the number of successful outcomes (which is 6) and divide it by the total number of possible outcomes (which is 36). Thus, the probability is:

[

\text{Probability} = \frac{\text{Number of successful outcomes}}{\text{Total outcomes}} = \frac{6}{36} = \frac{1}{6}.

]

This shows that the chance of rolling a sum of 7 when using two dice is indeed 1/6.