If X is a random variable and a, b are real numbers, then which of the following statements are true? (A) $\text{Var(aX+b)} = a^2 \text{Var(X)}$ Choose the correct answer from the options given below: |
(A) and (B) only (A) and (C) only (B) and (D) only (A), (C) and (D) only |
(A) and (B) only |
The correct answer is Option (1) → (A) and (B) only ** (A) $\text{Var}(aX+b)=a^{2}\,\text{Var}(X)$ → True (B) $E(aX+b)=a\,E(X)+b$ → True (C) $E(aX+b)=a\,E(X)-E(b)$ → False (because $E(b)=b$, so expression becomes $aE(X)+b$, not $aE(X)-b$) (D) $\text{Var}(aX+b)=a\,\text{Var}(X)+b$ → False (variance does NOT depend on $b$ and uses $a^{2}$, not $a$) Correct statements: (A) and (B) |