The probability of rolling a 4 on a standard six-sided die is calculated as follows:

1. Total possible outcomes: There are 6 faces on the die, so there are 6 possible outcomes (1, 2, 3, 4, 5, 6).
2. Favorable outcomes: There is only 1 face that shows a 4.

The probability $P$ of rolling a 4 is given by the formula:

$P(\text{rolling a 4}) = \frac{\text{Number of favorable outcomes}}{\text{Total possible outcomes}} = \frac{1}{6}$

Thus, the probability of rolling a 4 is $\frac{1}{6}$.

Would you like more details or have any questions? Here are some related questions you might consider:

1. What is the probability of rolling an even number?
2. How does the probability change if two dice are rolled?
3. What are the probabilities of rolling numbers other than 4?
4. How do you calculate the probability of rolling a specific number multiple times?
5. What is the difference between theoretical and experimental probability?

Tip: Always remember that the sum of probabilities for all possible outcomes of an event must equal 1.