defence exam Coast Guard Navik GD (General Duty) 02/2025 Mock Test Series Mathematics Statistics Variance and Standard Deviation
Consider 10 observation x1, x2,…., x10. such that \(\rm \sum_{i=1}^{10}(x_i-α)=2\ and\ \sum_{i=1}^{10}(x_i-β)^2=40\) where α, β are positive integers. Let the mean and the variance of the observations be\(\frac{6}{5}\ and\ \frac{84}{25}\) respectively. The \(\rm \frac{\beta}{\alpha}\) is equal to
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2
2
\(\frac{3}{2}\)
3
\(\frac{5}{2}\)
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1