Z-scores
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Question

A data set is normally distributed with the mean value $\mu = 70.00$ and standard deviation $\sigma = 11.00$. Find the z-score of the data value $x = 65.00$

z-score $z = \frac{x-\mu}{\sigma} = \frac{65.00 - 70.00}{11.00}=-0.45$