Conditional probability
What Conditional probability means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of Conditional probability
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Reference: AQA
The probability of an event given that another event has already occurred, found by restricting the sample space to that event.
Evaluates the likelihood of an event A occurring given that another event B has already occurred, denoted P(A|B).
The probability of A given that B has occurred, written P(A | B).
Topics that use Conditional probability
- M: Probability (AQA A-Level)
- Probability (Pearson Edexcel A-Level)
- Probability (A2 Unit 4: Applied Mathematics B) (WJEC A-Level)
Related terms
- Tree diagrams
- Two-way tables
- conditional probability formula
- Event
- Independent events
- mutually exclusive events
- sample space
- addition rule
Using Conditional probability in the exam
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