Hypothesis testing help


I have to: Identify the null hypothesis, Ho, the alternative hypothesis H1 and either identify the sampling distribution (normal, t, chi-square) of the test statistic, or state the methods should not be used and why for the following:

Claim: The population mean is 425. Sample data: n=18, x bar = 438, s=21.3. The data were taken from a simple random sample collected from a normally distributed population with a population standard deviaion of 18.4.

I have Ho: p = 425, and H1: p < 425. Is that correct? I am sure of the test statistic since the population is less than 30?

Any help would be great!



New Member
H0: p= 425 is right, but why would you set H1: p < 425 when Xbar is greater than 425? And you can use the test statistics even if the population is less than 30 when you know that the data is normally distributed.