The probability that an outcome of an event does not happen is calculated as follows:

\[ P(\text{A does not happen}) = 1-P(\text{A does happen}) \]

Probability space diagrams show every possible outcome of two events. They can also be used to calculate probabilities.

The number of times an outcome is expected to occur is calculated by multiplying the probability of the outcome occuring once by the number of times the event is repeated.

\[ \text{expectation} = P(\text{A}) \times \text{number of trials} \]

Example videos

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Practice questions

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