Question

Find z if X=27, μ=20, and α=3.4. Round to the nearest hundredth if necessary.

A. 2.06


B. –2.06


C. 1.18


D. 0.35

Answer 1

A.
`Z=2.06`

Explanation:

We want to find the Z-score of
`X=27` if the population mean is
`\mu=20`,and the population standard deviation is
`\sigma=3.4`.

We use the formula:

`Z=(X-\mu)/(\sigma)`

We substitute the values to obtain:

`Z=(27-20)/(3.4)`

`Z=(7)/(3.4)`

`Z=2.06`

The correct answer is A.