The probability of the occurrence of an event is `3/8`. Find the probability of the non-occurrence of the event.

Explanation

To find the probability of the non-occurrence of an event when the probability of occurrence is given, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Probability of Occurrence**:
We are given that the probability of occurrence of the event is \( P(A) = \frac{3}{8} \).

2. **Use the Complement Rule**:
The probability of the non-occurrence of the event (denoted as \( P(A') \)) can be found using the complement rule. The complement rule states that the sum of the probabilities of an event and its non-occurrence is equal to 1.
\[ P(A') = 1 - P(A) \]

3. **Substitute the Given Probability**:
Now, substitute the value of \( P(A) \) into the equation:
\[ P(A') = 1 - \frac{3}{8} \]

4. **Perform the Calculation**:
To perform the subtraction, convert 1 into a fraction with a denominator of 8:
\[ 1 = \frac{8}{8} \]
Now, subtract:
\[ P(A') = \frac{8}{8} - \frac{3}{8} = \frac{8 - 3}{8} = \frac{5}{8} \]

5. **Conclusion**:
Therefore, the probability of the non-occurrence of the event is:
\[ P(A') = \frac{5}{8} \]

### Final Answer:
The probability of the non-occurrence of the event is \( \frac{5}{8} \).

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