The following is a set of hypotheses, some information from one or more samples, and a standard error from a randomization distribution. Test H0: p 0.28 vs Ha: p 0.28 when the sample has n 900 , and p ^ 0.216 with SE 0.01 . Find the value of the standardized z -test statistic.

The value of the standardized z-test statistic is -6.4.

Step-by-step explanation:

The test statistic is:

In which X is the sample mean, is the value tested at the null hypothesis, and s is the standard error.

0.28 is tested at the null hypothesis:

This means that

p ^ 0.216 with SE 0.01

This means that

Then

The value of the standardized z-test statistic is -6.4.

a. she will receive a refund of $278.

step-by-step explanation: