To find the probability of both independent events A and B occurring at the same time, you multiply their individual probabilities together.
Given:
- \( P(A) = 0.3 \)
- \( P(B) = 0.25 \)
The probability of both A and B occurring, denoted as \( P(A \cap B) \), is calculated as follows:
\[ P(A \cap B) = P(A) \times P(B) \]
Substituting the values:
\[ P(A \cap B) = 0.3 \times 0.25 = 0.075 \]
Therefore, the probability of events A and B happening at the same time is \( \boxed{0.075} \).