Solveeit Logo

Question

Mathematics Question on Standard deviation

Which of the following is correct for standard deviation, where Xˉ\bar{X} = mean

A

σ=i=1n(XiXˉ)2n\sigma = \sqrt{\frac{ \sum_{i=1}^n (X_i - \bar{X})^2 }{n}}

B

σ=i=1n(XiXˉ)2n\sigma = \sqrt{\frac{\sum_{i=1}^n (X_i - \bar{X})^2 }{n}}

C

σ=i=1n((XiXˉ)2n)\sigma = \sqrt{ \sum_{i=1}^n \left(\frac{(X_i - \bar{X})^2}{n}\right) }

D

σ=i=1nXiXˉn\sigma = \sqrt{ \frac{\sum_{i=1}^n X_i - \bar{X}}{n} }

Answer

σ=i=1n(XiXˉ)2n\sigma = \sqrt{\frac{\sum_{i=1}^n (X_i - \bar{X})^2 }{n}}

Explanation

Solution

The correct option is (B) :σ=i=1n(XiXˉ)2n\sigma = \sqrt{\frac{\sum_{i=1}^n (X_i - \bar{X})^2 }{n}}