The variance sigma^2 of the data is . . . . | vedclass

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(B) First,calculate the mean $\overline{x}$:						$x_i$			$f_i$			$f_ix_i$			$f_ix_i^2$				$0$$3$$0$$0$		$1$$2$$2$$2$		$5$$3$$15$$75$		$6$$2$$12$$72$

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$29$

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(B) First,calculate the mean $\overline{x}$:						$x_i$			$f_i$			$f_ix_i$			$f_ix_i^2$				$0$$3$$0$$0$		$1$$2$$2$$2$		$5$$3$$15$$75$		$6$$2$$12$$72$		$10$$6$$60$$600$		$12$$3$$36$$432$		$17$$3$$51$$867$		Total$\sum f_i = 22$$\sum f_ix_i = 176$$\sum f_ix_i^2 = 2048$	$\overline{x} = \frac{\sum f_i x_i}{\sum f_i} = \frac{176}{22} = 8$Variance $\sigma^2 = \frac{1}{N} \sum f_i x_i^2 - (\overline{x})^2$$\sigma^2 = \frac{2048}{22} - (8)^2$$\sigma^2 = 93.09 - 64 = 29.09$Rounding to the nearest integer,the correct option is $B$.

The variance $\sigma^2$ of the data is $ . . . . . .$

$x_i$ $0$ $1$ $5$ $6$ $10$ $12$ $17$

$f_i$ $3$ $2$ $3$ $2$ $6$ $3$ $3$

Similar Questions

The standard deviation of the data $6, 7, 8, 9, 10$ is

If $x_1, x_2, x_3, \ldots, x_n$ are $n$ observations such that $\sum(x_i+2)^2 = 28n$ and $\sum(x_i-2)^2 = 12n$,then the variance is:

In a series of $2n$ observations,half of them are equal to $a$ and the remaining half are equal to $-a$. If the standard deviation of the observations is $2$,then $|a|$ equals:

The coefficient of variation for the following data is:
$x_i$ $5$ $7$ $9$ $11$
$f_i$ $3$ $2$ $1$ $2$

The mean of a set of $10$ observations is $5$ and the standard deviation is $2\sqrt{6}$. If the mean of another set of $20$ observations is $5$ and the standard deviation is $3\sqrt{2}$,what is the standard deviation of the combined set of $30$ observations?

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The variance $\sigma^2$ of the data is $ . . . . . .$ $x_i$ $0$ $1$ $5$ $6$ $10$ $12$ $17$ $f_i$ $3$ $2$ $3$ $2$ $6$ $3$ $3$