If x_1, x_2,.....x_n are n observations such | vedclass

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Question

Use $: \sigma^{2} \geq 0$

$ \Rightarrow \frac{\sum x_{i}^{2}}{n}-\left(\frac{\sum x_{i}}{n}\right)^{2} \geq 0$

$\Rightarrow \quad \frac{400}{n}-

Vedclass · Accepted Answer

$27$

Vedclass · Answer

Use $: \sigma^{2} \geq 0$

$ \Rightarrow \frac{\sum x_{i}^{2}}{n}-\left(\frac{\sum x_{i}}{n}\right)^{2} \geq 0$

$\Rightarrow \quad \frac{400}{n}-\frac{10000}{n^{2}} \geq 0 $

$\Rightarrow n \geq 25$

Classes	$30-40$	$40-50$	$50-60$	$60-70$	$70-80$	$80-90$	$90-100$
${f_i}$	$3$	$7$	$12$	$15$	$8$	$3$	$2$

class	$0-10$	$10-20$	$20-30$	$30-40$
Freq	$1$	$3$	$4$	$2$

Class	$10-20$	$20-30$	$30-40$
Frequency	$2$	$x$	$2$

If $x_1, x_2,.....x_n$ are $n$ observations such that $\sum\limits_{i = 1}^n {x_i^2} = 400$ and $\sum\limits_{i = 1}^n {{x_i}} = 100$ , then possible value of $n$ among the following is

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