Target Exam

CUET

Subject

-- Applied Mathematics - Section B2

Chapter

Inferential Statistics

Question:

Which of the following statements are TRUE?

(A) The variable t of t-distribution ranges from $-∞$ to $∞$.
(B) The probability curve of the t-distribution is symmetric about the line $t=0$
(C) The variance of the t-distribution is greater than one.
(D) As the number of degrees of freedom decreases, the t-distribution curve moves closer to the standard normal probability curve.

Choose the correct answer from the options given below:

Options:

(A), (B) and (D) only

(A), (B) and (C) only

(A), (B), (C) and (D)

(C) and (D) only

Correct Answer:

(A), (B) and (C) only

Explanation:

The correct answer is Option (2) → (A), (B) and (C) only **

(A) True. The t-statistic ranges over the entire real line: $(-\infty,\infty)$.

(B) True. The t-distribution is symmetric about $t=0$.

(C) True for all degrees of freedom $v>2$. Variance of t-distribution is $\frac{v}{v-2}$, which is always greater than 1.

(D) False. As degrees of freedom increase, the t-distribution approaches the standard normal curve. If degrees of freedom decrease, it becomes wider, not closer.

Correct statements: (A), (B), (C)