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Standard deviation property: σ(aX + b) =
Ab
Ba²σ
C|a| σ (translation b doesn't affect SD; scaling does)
Daσ + b
Answer & Solution
Correct answer: C. |a| σ (translation b doesn't affect SD; scaling does)
SD invariant under translation: σ(X + b) = σ(X). Scales linearly: σ(aX) = |a| σ(X). So σ(aX + b) = |a| σ(X). Useful for unit conversions.
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