Question

The standard deviation of $10,16,10,16,10,10,16,16$ is?

• A. $4$
• B. $6$
• C. $3$
• D. $0$

Answer 1

The correct option is C $3$

Assume $A=13;$ hence $d=A-13$

x	d	$d^2$
$10$	$-3$	$9$
$16$	$3$	$9$
$10$	$-3$	$9$
$16$	$3$	$9$
$10$	$-3$	$9$
$10$	$-3$	$9$
$16$	$-3$	$9$
$16$	$3$	$9$
	$\sum d=0$	$\sum d^2=72$

Use following formula:
$\sqrt{\frac{\sum d^2}{n}-{\left[\frac{\sum d}{n}\right]}^2}$
$\sqrt{\frac{72}{8}-{\left[\frac{0}{8}\right]}^2}$
$\sqrt{9}$
$=3$.