Find the mean and variance for the following | vedclass

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

Vedclass · Accepted Answer

Mean: $19$,Variance: $43.4$

Vedclass · Answer

(A) First,we calculate the mean $\bar{x} = \frac{\sum f_i x_i}{N}$.						$x_i$			$f_i$			$f_i x_i$			$(x_i - \bar{x})^2$			$f_i(x_i - \bar{x})^2$				$6$$2$$12$$169$$338$		$10$$4$$40$$81$$324$		$14$$7$$98$$25$$175$		$18$$12$$216$$1$$12$		$24$$8$$192$$25$$200$		$28$$4$$112$$81$$324$		$30$$3$$90$$121$$363$		Total$N=40$$\sum f_i x_i = 760$-$\sum f_i(x_i - \bar{x})^2 = 1736$	Mean $\bar{x} = \frac{760}{40} = 19$.Variance $\sigma^2 = \frac{1}{N} \sum f_i(x_i - \bar{x})^2 = \frac{1736}{40} = 43.4$.

Find the mean and variance for the following data:

$x_i$ $6$ $10$ $14$ $18$ $24$ $28$ $30$

$f_i$ $2$ $4$ $7$ $12$ $8$ $4$ $3$

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Find the mean and variance for the following data: $x_i$ $6$ $10$ $14$ $18$ $24$ $28$ $30$ $f_i$ $2$ $4$ $7$ $12$ $8$ $4$ $3$