The AND / OR Rules (AQA GCSE Maths): Flashcards

Events where one doesn't affect the probability of the other

Events where one affects the probability of the other

$P(A \text{ and } B) = P(A) \times P(B)$

When you want both events to happen

$P(A \text{ or } B) = P(A) + P(B) - P(A \text{ and } B)$

Events that cannot happen together

$P(A \text{ or } B) = P(A) + P(B)$

To avoid double-counting the overlap

and, both, all

or, either, at least one