Question

You roll two fair dice, one green and one red. What is the probability of rolling a sum of 7?

1) 1/6
2) 1/12
3) 1/36
4) 1/18

Answer 1

To find the probability of rolling a sum of 7 when rolling two fair dice, we consider the possible outcomes. There are 6 outcomes that result in a sum of 7 out of a total of 36 possible outcomes. The probability of rolling a sum of 7 is 1/6.

Step-by-step explanation:

To find the probability of rolling a sum of 7, we need to determine how many outcomes out of the total number of possible outcomes result in a sum of 7. Let's consider the possibilities:

1. Rolling a 1 on the green die: The red die must then roll a 6 (1/6 chance).

2. Rolling a 2 on the green die: The red die must then roll a 5 (1/6 chance).

3. Rolling a 3 on the green die: The red die must then roll a 4 (1/6 chance).

4. Rolling a 4 on the green die: The red die must then roll a 3 (1/6 chance).

5. Rolling a 5 on the green die: The red die must then roll a 2 (1/6 chance).

6. Rolling a 6 on the green die: The red die must then roll a 1 (1/6 chance).

Therefore, there are 6 possible outcomes resulting in a sum of 7 out of 36 total possible outcomes. The probability of rolling a sum of 7 is 6/36, which simplifies to 1/6.