Tree Diagrams (Edexcel GCSE Maths): Flashcards

Visual tool for probability with multiple events

1

Multiply probabilities along the path

All end probabilities must sum to 1

Add relevant end probabilities together

Remain the same for each selection

Each selection is independent of previous ones

Change after each selection

Conditional probabilities

$1 - P(\text{none})$

Multiply along branches, add across outcomes

With: same probabilities; without: probabilities change