Question

Suppose a population $A$ has 100 observations $101, 102,..., 200$ and another population $B$ has $100$ observations $151, 152, ..., 250.$ If $V_A$ and $V_B$ represent the variances of the two population respectively, then $\frac{V_{A}}{V_{B}}$ is :

• A. $\frac{9}{4}$
• B. $\frac{4}{9}$
• C. $\frac{2}{3}$
• D. $1$

Answer 1

Answer: (D)

$1$

Answer 2

Since variance is independent of change in origin. Hence variance of observations 101,102, ..... ,200 is same as variance of 151,152, ..., 250 $\therefore V_{A}=V_{B}$ $\Rightarrow \frac{V_{A}}{V_{B}}=1$