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Flip to reveal answersState the formula for E(X).
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All 3 Flashcards — Expected value
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Question
State the formula for E(X).
Answer
E(X) = Σ x·P(X = x).
Question
What does E(X) represent?
Answer
The expected (mean) value — the long-run average of X.
Question
Can E(X) be a value X never takes?
Answer
Yes — it's an average, so it can be a non-outcome value like 2.7.
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Full study notes for Expected value
Topic 4.7 hub
Discrete random variables
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