Refer to the Current Allergy & Clinical Immunology (March 2004) study of n = 46 hospital employees who were diagnosed with a latex allergy from exposure to the powder on latex gloves, presented in Exercise. The number of latex gloves used per week by the sampled workers is summarized as follows: x = 19.3 and s = 11.9. Let m represent the mean number of latex gloves used per week by all hospital employees.

Consider testing H0: µ = 20 against Ha: µ < 20.

a. Give the rejection region for the test at a significance level of α = .01.

b. Calculate the value of the test statistic.

c. Use the results from parts a and b to draw the appropriate conclusion.