Let x 1 , x 2 , . . . . , x n be n observations such that ∑ x i 2 = 400 and ∑ x i = 40 , then a possible value of n among the following is

Step-by-step solution

Since, variance is always greater than or equal to zero hence x 1 2 + x 2 2 + ... + x n 2 n ≥ x ⁡ 1 + x 2 + ... + x n n 2 ⇒ 4 0 0 n ≥ 1 6 0 0 n 2 ⇒ n ≥ 4