In the derivation of population variance for an ungrouped data set

MATHEMATICS · Single correct · CBSE · Mathematics · Statistics · Statistics

Problem

In the derivation of population variance for an ungrouped data set, the value of

\sum_{i=1}^{n}(x_i-\bar{x})

is required. Which of the following equals this sum? (a)

\displaystyle \sum_{i=1}^{n}x_i

(b)

n\bar{x}

\bar{x}