# Once you have a z-score, how do you calculate the value that is found in the z-tables?

##### 1 Answer

The Z-score value is the distance between the raw score or an individual member to the population mean in terms of Standard Deviations.

#### Explanation:

A *standard normal table* , also called the unit normal table or **Z table** , is a mathematical table for the *values of Φ* , which are the values of the cumulative distribution function of the normal distribution (that's why we use the precalculated tables instead of generating them each time).

Examples:

http://www.stat.ufl.edu/~athienit/Tables/Ztable.pdf

Actual formula:

http://math.tutorvista.com/statistics/z-score-table.html

https://www.mathsisfun.com/data/standard-normal-distribution-table.html

Here's a couple of good guides:

https://www.easycalculation.com/statistics/z-score-standard.php

(read below the calculator for the description).