In 2011, the national percent of low-income working families had an approximately normal distribution with a mean of 31.3% (The Working Poor Families Project, 2011). Although it has remained slow, some politicians now claim that the recovery from the Great Recession has been steady and noticeable. As a result, it is believed that the national percent of low-income working families was significantly lower in 2014 than it was in 2011. To support this belief, a spring 2014 sample of n=16 jurisdictions produced a sample mean of 29.8% for the percent of low income working families, with a sample standard deviation of 4.1%. Using a 0.05 significance level, test the claim that the national average percent of low-income working families has improved since 2011.
10. Write a few brief sentences stating the type of test that should be performed, explaining why that test is the appropriate test.
11. Identify and state the null and alternate hypothesis for this test.
12. Determine the test statistic by hand and determine the P-value associated with your hypothesis test. Clearly state these values.
13.State the decision of the hypothesis test based on a 0.05 significance level.
14. Provide the appropriate conclusion about the claim that the national average percent of low-income working families had improved by 2014.
