Question

An employment information service claims the mean annual salary for full-time female workers over age 25 and without a high school diploma is $18,500. The annual salaries for a random sample of 12 full-time female workers without a high school diploma are shown below.

Salaries
19,665	21,354	20,177	19,794	19,316	22,445
21,864	17,312	20,143	18,328	20,403	20,237

Instructions: Round all your math steps to two decimal places just like I have been doing in class.

a. Compute the value of the test statistic. (Round to two decimal places) Answer

b. At α=0.05, test the claim that the mean salary is more than $18,500. What is your conclusion? Answer

Answer 1

a)

H0 : mu = 18500
Ha: mu > 18500

from the given data,

xbar =20086.50
s = 1417.74

t = (xbar - mu)/(sigma/sqrt(n))
= ( 20086.50- 18500)/(1417.74/sqrt(12))
= 3.88

p value = 0.0013

b)

Reject H0 as p value < 0.05