Equally Likely Outcomes
When all outcomes in a sample space are equally likely, the probability of each outcome is 1/n where n is the total number of outcomes. For any event A with k favorable outcomes, P(A) = k/n.
Real World
The UK National Lottery draw uses numbered balls in identical conditions so each ball has an equally likely chance of selection, making probability calculations straightforward and fair.
Exam Focus
Check whether equally likely outcomes are stated or implied — if not stated, you cannot use P(A) = k/n directly.
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