Using the z-distribution, it is found that the z-value is of z = -2.29.
<h3>How to find the critical value of Z?</h3>
For a confidence level of
, it is Z with a p-value of
.
We have a 97.8% confidence level, hence
, z is the value of Z that has a p-value of
, so the critical value is z = -2.29.
More can be learned about the z-distribution at brainly.com/question/25890103