The Department of Economic and Community Development (DECD) reported that in 2009 the average number of new jobs created per county was 450. The department also provided the following information regarding a sample of 5 counties in 2010.
County New Jobs Created In 2010
a. Compute the sample average and the standard deviation for 2010.
b. We want to determine whether there has been a significant decrease in the average number of jobs created. Provide the null and the alternative hypotheses.
c. Compute the test statistic.
d. Compute the p-value; and at 95% confidence, test the hypotheses. Assume the population is normally distributed.
Step by step method for computing test statistic for One sample t test is given in the answer.