Let x₁, x₂,........,xₙ be n observations such that Σ {{xᵢ}^2 = 300} and Σ {{x?

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13.Statistics

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Let $x_1, x_2,........,x_n$ be $n$ observations such that $\sum {{x_i}^2 = 300} $ and $\sum {{x_i} = 60} $ on value of $n$ among the following is

A

$5$

B

$10$

C

$15$

D

None of these

Solution

$\frac{\Sigma \mathrm{x}_{\mathrm{i}}^{2}}{\mathrm{n}} \geq\left(\frac{\Sigma \mathrm{x}_{\mathrm{i}}}{\mathrm{n}}\right)^{2}$

$\frac{300}{n} \geq\left(\frac{60}{n}\right)^{2}$

$n \geq 12$

Standard 11

Mathematics

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