Question

A set of data items is normally distributed with a mean of 90 and a standard deviation of 8. Convert 86 to a z-score.

Answer 1

Step-by-step explanation

We are to find the z-score for the given data

To do so, we will use the formula:

`z=(x-\mu)/(\sigma)`

where

`\begin{gathered} x=observed\text{ mean=86} \\ \mu=90 \\ \sigma=8 \end{gathered}`

Therefore,

`\begin{gathered} z_(86)=(86-90)/(8)=-(4)/(8)=-0.5 \\ \\ z_(86)=-0.5 \end{gathered}`

The z-score is -0.5