Question

The z value for a 97. 8% confidence interval estimation is.

Answer 1

Using the z-distribution, it is found that the z-value is of z = -2.29.

How to find the critical value of Z?

For a confidence level of $\alpha$, it is Z with a p-value of $\frac{1 + \alpha}{2}$.

We have a 97.8% confidence level, hence$\alpha = 0.978$, z is the value of Z that has a p-value of $\frac{1+0.978}{2} = 0.989$, so the critical value is z = -2.29.

More can be learned about the z-distribution at brainly.com/question/25890103