mutually exclusive events
What mutually exclusive events means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of mutually exclusive events
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Reference: WJEC
Two events A and B are mutually exclusive if they cannot occur simultaneously, meaning A ∩ B = ∅ and P(A ∩ B) = 0.
Events that cannot occur together, so for events A and B, P(A ∩ B) = 0 and P(A ∪ B) = P(A) + P(B).
Two events that cannot happen at the same time, so P(A and B) = 0 and P(A or B) = P(A) + P(B).
Events that satisfy A ∩ B = ∅ so P(A ∩ B) = 0.
Topics that use mutually exclusive events
- M: Probability (AQA A-Level)
- Probability (Pearson Edexcel A-Level)
- Overarching themes - Mathematical argument, language and proof (WJEC A-Level)
- Probability (AS Unit 2: Applied Mathematics A) (WJEC A-Level)
Related terms
- Independent events
- sample space
- addition rule
- Conditional probability
- Event
- Intersection
- multiplication rule
- Tree diagrams
Using mutually exclusive events in the exam
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