A study was conducted on a sample of 27 records of patients seen at a chronic disease hospital on an outpatient basis. The mean number of monthly outpatient visits per patient was 4.8 with estimated standard deviation of 2.2. Assuming that the population distribution is normal, the hospital is particularly interested in testing the claim that the mean number of hospital visits is greater than 4. Test this claim at 5% significance in the following questions.

22. What are the null and alternative hypotheses?

23. What is the critical value for the test?

24. What is the value of the test statistic?

25. What conclusion should you make based on the given data?