What is the probability of an impossible event?

Answer

To find the probability of an impossible event, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Probability**:
- Probability is defined as the ratio of the number of favorable outcomes to the total number of possible outcomes.

2. **Identify the Event**:
- In this case, we are looking for the probability of rolling a 7 on a standard six-sided die.

3. **Determine the Total Outcomes**:
- A standard die has 6 faces, which are numbered 1, 2, 3, 4, 5, and 6. Therefore, the total number of possible outcomes when rolling a die is 6.

4. **Identify Favorable Outcomes**:
- To find the probability of rolling a 7, we need to identify how many outcomes are favorable. Since a standard die does not have a face with the number 7, the number of favorable outcomes is 0.

5. **Calculate the Probability**:
- Using the probability formula:
\[ \text{Probability of an event} = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} \]
- Substitute the values:
\[ \text{Probability of rolling a 7} = \frac{0}{6} = 0 \]

6. **Conclusion**:
- The probability of an impossible event, such as rolling a 7 on a six-sided die, is 0.

### Final Answer:
The probability of an impossible event is 0.

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