If σ A,σ B,σ C are the variance of heights of students of three sections each containing 10 students as follows:

Question

If σ A,σ B,σ C are the variance of heights of students of three sections each containing 10 students as follows: <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/mathematics/c0b968896ac28eb8d6b52a0b6fe2b378-.png" /> (A) 1:2:3 (B) 2:3:4 (C) 1:1:1 (D) 1:2:4

Tardigrade Admin · Accepted Answer

If each observation is increased by a same quantity, then the variance remains unchanged. ∴ σ A:σ B:σ C=1:1:1 .

Q. If $σ_{A}, σ_{B}, σ_{C}$ are the variance of heights of students of three sections each containing $10$ students as follows:

$1 : 2 : 3$

$2 : 3 : 4$

$1 : 1 : 1$

$1 : 2 : 4$

If each observation is increased by a same quantity, then the variance remains unchanged.
$∴ σ_{A} : σ_{B} : σ_{C} = 1 : 1 : 1$ .

Q. If σA​,σB​,σC​ are the variance of heights of students of three sections each containing 10 students as follows:

1:2:3

2:3:4

1:1:1

1:2:4