Examples of what pupils should know and be able to do
Pupils need to know that the probabilities of two, or more, independent events can be multiplied together to obtain the probability of both, or all, occurring.
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Using both of the above, pupils should be able to construct a probability tree diagram.
Using a tree diagram depicting rain and not rain on two days in the week, the probability of it raining on just one of the two days can be found by adding together the probabilities for [rain and not rain] and [not rain and rain].
Probing questions
If I throw a coin and roll a dice is the probability of a head and a 2 more or less than that of either of them?
If I throw a coin and roll a dice what is the probability of a 5 and a head?
What if pupils find this a barrier?
Use a possibility space to list all possible combinations of, for example, score on a dice and heads or tails. Show how a particular event is formed by a multiplication of two fractions.