Question

A claim is made that the average salary for all jobs in Minnesota is less than $74,500. You are going to test the claim using α=0.05 and assume that your data is normally distributed and the population standard deviation (σ) is not known.

Here is the data I came up with in Excel for a Hypothesis test.

Calculations/Values	Formulas/Answers
Mean (x-bar)	72027.32418
Standard Deviation	22728.49557
n	364
mu
Test Statistic	-312.9194042
Critical Value	1.644853627
P-value

	Salary
Mean	72027.32418
Known Variance	22728.49557
Observations	364
Hypothesized Mean	74500
z	-312.9194042
P(Z<=z) one-tail
z Critical one-tail	1.644853627

I need help determining if I should reject the null hypothesis based on the critical value approach and if the p-value matches the conclusion based on that method.  

Answer 1

critical value (-) for left tail (+) for right tail