What would you like to understand?

Swapping the events changes both the numerator and the denominator in the conditional probability formula. $P(A\mid B)$ uses $P(A \cap B)$ as the numerator and $P(B)$ as the denominator, whereas $P(B\mid A)$ uses $P(A \cap B)$ as the numerator but $P(A)$ as the denominator.

Conditions: Events A and B have different marginal probabilities ($P(A) \neq P(B)$).; Both events have positive probability.

Swapping the events changes both the numerator and the denominator in the conditional probability formula. $P(A\mid B)$ uses $P(A \cap B)$ as the numerator and $P(B)$ as the denominator, whereas $P(B\mid A)$ uses $P(A \cap B)$ as the numerator but $P(A)$ as the denominator.

Conditions: Events A and B have different marginal probabilities ($P(A) \neq P(B)$).; Both events have positive probability.