The variance of a set of 8 observations is 16. If each observation is multiplied by -2, what is the variance of the new set of observations?
Answer and explanation
Correct answer: A. 64
- Step 1: Property: Var(a X) = a^2 Var(X).
- Step 2: Here a = -2.
- Step 3: Var(new) = (-2)^2 16 = 4 16 = 64.
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