Question 40

Mathematics Statistics Easy

If each observation of a Row data whose variance is \( \sigma^{2} \) is multiplied by \( h \) , then the variance of the new set is

(A) \( \sigma^{2} \)
(B) \( h^{2} \sigma^{2} \)
(C) \( h \sigma^{2} \)
(D) \( h+\sigma^{2} \)
View Dynamic Solution & Explanation
Correct Solution: Option B

Step-by-step Solution:

The variance of a linear transformation of a random variable follows the rule: \[ \text{Var}(ax + b) = a^2 \cdot \text{Var}(x) \] Given that \( a = h \) and \( b = 0 \), we apply this property: \[ \text{Var}(h \cdot x) = h^2 \cdot \text{Var}(x) \] Since \( \text{Var}(x) = \sigma^2 \), we get: \[ \text{Var}(h \cdot x) = h^2 \sigma^2 \]