Tree diagrams
What Tree diagrams means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of Tree diagrams
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Reference: Pearson Edexcel
Show sequential events, with branch probabilities multiplied along a path and added across paths, and the second set of branches carries conditional probabilities.
Probabilities on secondary branches represent conditional probabilities, and the path probability is P(A ∩ B) = P(B) × P(A|B).
A representation in which probabilities on the second set of branches are conditional on the first outcome.
Topics that use Tree diagrams
- M: Probability (AQA A-Level)
- Probability (Pearson Edexcel A-Level)
- Probability (A2 Unit 4: Applied Mathematics B) (WJEC A-Level)
Related terms
- Conditional probability
- Two-way tables
- conditional probability formula
- Event
- Independent events
- mutually exclusive events
- sample space
- addition rule
Using Tree diagrams in the exam
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