Variance:
Asqrt(SD)
Bmean of squares
CΣ(x - x̄)² / n (square of SD)
D|x - x̄|
Answer & Solution
Correct answer: C. Σ(x - x̄)² / n (square of SD)
Var = σ² = Σ(x - x̄)²/n. Average squared deviation from mean. Also = E[X²] - (E[X])². Always ≥ 0.
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