Question

Find the Variance and Standard Deviation of the values $4,4,4,4,4,4$ using short-cut method.

• A. $4$
• B. $0$
• C. $12$
• D. None of these

Answer 1

The correct option is B $0$

For $4,4,4,4,4,4$

$\stackrel{\_}{x}=\frac{4+4+4+4+4+4}{6}=4$

$x_i-\stackrel{\_}{x}=4-4=0$

Variance $={\sigma }^2=\frac{\sum {(x_i-\stackrel{\_}{x})}^2}{n-1}=\frac{0}{6-1}=0$

Standard deviation $=\sigma =\sqrt{\frac{\sum {(x_i-\stackrel{\_}{x})}^2}{n-1}}=0$

So, option $B$ is correct.