Mathematics A-Level
general addition rule
What general addition rule means in Mathematics A-Level, as defined for WJEC.
Definition of general addition rule
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Reference: WJEC
States that P(A ∪ B) = P(A) + P(B) − P(A ∩ B), used in combination with the multiplication rule to solve multi-step probability problems.
Topics that use general addition rule
- Probability (A2 Unit 4: Applied Mathematics B) (WJEC A-Level)
Related terms
- Conditional probability
- conditional probability formula
- evaluating assumptions
- independence violations
- model refinement
- probabilistic modelling
- Tree diagrams
- Two-way tables
Using general addition rule in the exam
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