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(A) First,we calculate the mean $\bar{x} = \frac{\sum f_i x_i}{\sum f_i}$.						$x_i$			$f_i$			$f_i x_i$			$(x_i - \bar{x})^2$			$f_i(x_i - \bar{x})^

Vedclass · Accepted Answer

Variance $= 45.8$,Standard Deviation $\approx 6.77$

Vedclass · Answer

(A) First,we calculate the mean $\bar{x} = \frac{\sum f_i x_i}{\sum f_i}$.						$x_i$			$f_i$			$f_i x_i$			$(x_i - \bar{x})^2$			$f_i(x_i - \bar{x})^2$				$4$$3$$12$$100$$300$		$8$$5$$40$$36$$180$		$11$$9$$99$$9$$81$		$17$$5$$85$$9$$45$		$20$$4$$80$$36$$144$		$24$$3$$72$$100$$300$		$32$$1$$32$$324$$324$		Total$30$$420$-$1374$	Mean $\bar{x} = \frac{420}{30} = 14$.Variance $(\sigma^2) = \frac{\sum f_i(x_i - \bar{x})^2}{N} = \frac{1374}{30} = 45.8$.Standard Deviation $(\sigma) = \sqrt{45.8} \approx 6.77$.

Find the variance and standard deviation for the following data:

$x_i$ $4$ $8$ $11$ $17$ $20$ $24$ $32$

$f_i$ $3$ $5$ $9$ $5$ $4$ $3$ $1$

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Find the variance and standard deviation for the following data: $x_i$ $4$ $8$ $11$ $17$ $20$ $24$ $32$ $f_i$ $3$ $5$ $9$ $5$ $4$ $3$ $1$