(4g) know when to add or multiply two probabilities: if A and B are mutually exclusive, then the probability of A or B occurring is P(A) + P(B), whereas if A and B are independent events, the probability of A and B occurring is P(A) x P(B)
(4h) use tree diagrams to represent outcomes of compound events, recognising when events are independent

Wales

Key Stages 3 and 4

(2.5) identify all the outcomes of a combination of two experiments; use tabulation and tree diagrams (KS3)
(2.6) recognise the conditions when the addition of probabilities for mutually exclusive events, and the multiplication of probabilities for two independent events, apply, and make the appropriate calculations (KS3)

(3c) identify all the outcomes when dealing with a combination of two independent events using diagrams or tables and use these to find probabilities
know that if there are several outcomes of an event (exhaustive and mutually exclusive), the total of their probabilities is 1
understand that the probability of something happening is 1 minus the probability of it not happening
understand and apply the addition of probabilities for mutually exclusive events
understand that when dealing with two independent events, the probability of them both happening is less than the probability of either one of them happening (unless the probability is 0 or 1)
calculate the probability of a combined event given the probability of two independent events and illustrate combined probabilities of several events using tabulation or a tree diagram
produce a tree diagram to illustrate the combined probability of several events which are not independent