Reversing Conditional Probability: From P(A|B) to P(B|A)
Use the definition of conditional probability to find P(B|A) when P(A|B) is known.

Use the definition of conditional probability to find P(B|A) when P(A|B) is known.
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11th Grade · Math · CCSS
5 lessons
Learners will apply conditional probability to real-world contexts, reverse conditional probabilities, and solve multi-step problems.
Find the conditional probability of A given B as the fraction of B's outcomes that also belong to A, and interpret the answer in terms of the model.
Understand the conditional probability of A given B as P(A and B)/P(B), and interpret independence of A and B as saying that the conditional probability of A given B is the same as the probability of A, and the conditional probability of B given A is the same as the probability of B.