Standard deviation, Normal Distributions and Taking Random Samples

[DarcyDorian]

Find the standard score for a the data value 9 from a normal distribution which has a
mean of 16.8 and a standard deviation of 2.3

 

[MarkFL]

Hello and welcome to MHB, DarcyDorian! :D

We ask that our users show their progress (work thus far or thoughts on how to begin) when posting questions. This way our helpers can see where you are stuck or may be going astray and will be able to post the best help possible without potentially making a suggestion which you have already tried, which would waste your time and that of the helper.

Assuming you don't know how to begin, we will need the following formula:

[box=green]

The Normal Distribution​

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$z$-score for an $x$-value: $$z=\frac{x-\mu}{\sigma}$$[/box]

Now, we are given $x=9$, $\mu=16.8$ and $\sigma=2.3$, so can you use the above formula to compute $z$ (the standard score)? :)