The mean and variance of n observations x_1, | vedclass

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(D) The variance of $n$ observations is given by the formula $\sigma^2 = \frac{1}{n} \sum_{i=1}^n x_i^2 - (\bar{x})^2$,where $\bar{x}$ is the mean of

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$16$

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(D) The variance of $n$ observations is given by the formula $\sigma^2 = \frac{1}{n} \sum_{i=1}^n x_i^2 - (\bar{x})^2$,where $\bar{x}$ is the mean of the observations.Given that the mean $\bar{x} = 5$,variance $\sigma^2 = 0$,and $\sum_{i=1}^n x_i^2 = 400$.Substituting these values into the formula:$0 = \frac{1}{n}(400) - (5)^2$$0 = \frac{400}{n} - 25$$\frac{400}{n} = 25$$n = \frac{400}{25} = 16$Thus,the value of $n$ is $16$.

Class interval	$0-10$	$10-20$	$20-30$	$30-40$
Frequency	$1$	$3$	$4$	$2$

The mean and variance of $n$ observations $x_1, x_2, x_3, \ldots, x_n$ are $5$ and $0$ respectively. If $\sum_{i=1}^n x_i^2 = 400$,then the value of $n$ is equal to

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