Gujarati
Hindi
13.Statistics
normal

Let $x_1, x_2, x_3, x_4, .......... , x_n$ be $n$ observations and let $\bar x$ be their arithmetic mean and $\sigma ^2$ be their variance.

Statement $-1$ : Variance of observations $2x_1, 2x_2, 2x_3, ......, 2x_n$ is $4\sigma ^2$ .

Statement $-2$ : Arithmetic mean of $2x _1, 2x_2, 2x_3, ......, 2x_n$ is $4\bar x$ .

A

Statement $-1$ is true, statement $-2$ is true and statement $-2$ is $NOT$ the correct explanation for statement $-1$

B

Statement $-1$ is true, statement $-2$ is false

C

Statement $-1$ is false, stateemnt $-2$ is true

D

Statement $-1$ is true, statement $-2$ is true and statement $-2$ is correct explanation for statement $-1$

Solution

If each observations is multiplied by a constant $k$ then their mean is multiplied with $k$ and their variance is multiplied by $k^2$ .

Standard 11
Mathematics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.