addition rule
What addition rule means in Mathematics A-Level, as defined for AQA, WJEC.
Definitions of addition rule
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Reference: AQA
For mutually exclusive events, the probability of A or B is found by adding their probabilities.
For mutually exclusive events the addition rule simplifies to P(A ∪ B) = P(A) + P(B).
Topics that use addition rule
- M: Probability (AQA A-Level)
- Probability (AS Unit 2: Applied Mathematics A) (WJEC A-Level)
Related terms
- Independent events
- multiplication rule
- mutually exclusive events
- Complement
- Conditional probability
- conditional probability formula
- Critiquing assumptions
- Effect on calculated probabilities
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