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EasyStatistics

Variance of a Scaled Variable

Goldman Sachs

If Var(X) = 3, what is Var(2X)?

Approach

Var(aX) = a²·Var(X).

Range of CorrelationNext: Correlation of X and X²

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Variance of Uniform(0,1)EasyVariance of a SumEasyCentral Limit TheoremEasyCovariance of a Linear TransformMediumRange of CorrelationEasyCorrelation of X and X²Medium

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