A telephone service representative believes that the proportion of customers completely satisfied with their local telephone service is different between the South and the Northeast. The representative's belief is based on the results of a survey. The survey included a random sample of 700 southern residents and 580 northeastern residents. 49% of the southern residents and 42% of the northeastern residents reported that they were completely satisfied with their local telephone service. Find the 80% confidence interval for the difference in two proportions. Step 1 of 3: Find the critical value that should be used in constructing the confidence interval. Step 2 of 3: Find the value of the standard error. Round your answer to three decimal places Step 3 of 3: Construct the 80% confidence interval. Round your answers to three decimal places.
A telephone service representative believes that the proportion of customers completely satisfied with their local telephone service is different between the South and the Northeast. The representative's belief is based on the results of a survey. The survey included a random sample of 700 southern residents and 580 northeastern residents. 49% of the southern residents and 42% of the northeastern residents reported that they were completely satisfied with their local telephone service. Find the 80% confidence interval for the difference in two proportions.
Find the critical value that should be used in constructing the confidence interval.
Find the value of the standard error. Round your answer to three decimal places
Construct the 80% confidence interval. Round your answers to three decimal places.
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