# Conditional Probability

If A and B are two events of the same sample, S, then:

The conditional probability of event A on B, **P (A|B)**, is the probability of event A when the event of B has already occurred.

#### Example

Calculate the probability of a 6 being rolled by a die if it is already known that the result is even.

#### Independent Events

Two events A and B are independent if:

**p(A|B) = p(A)**

#### Dependent Events

Two events A and B are dependent if:

**p(A|B) ≠ p(A)**

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