THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
A supermarket chain has 25 stores in the North,30 in the South,50 in the Midwest,and 35 in the West.Using a proportional allocation of a random sample of 30% of the outlets,the manager records the following means and standard deviations.

-Find a 95% confidence interval for the population mean.
A)142.69 ± 5.22
B)142.69 ± 1.96
C)142.69 ± 2.66
D)142.69 ± 4.58

Question

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
A supermarket chain has 25 stores in the North,30 in the South,50 in the Midwest,and 35 in the West.Using a proportional allocation of a random sample of 30% of the outlets,the manager records the following means and standard deviations.
 
-Find a 95% confidence interval for the population mean.
A)142.69 ± 5.22 
B)142.69 ± 1.96 
C)142.69 ± 2.66 
D)142.69 ± 4.58

Quizplus · Accepted Answer

The correct choice is A) 142.69 ± 5.22 because a confidence interval for the population mean is typically expressed in the form of (mean ± margin of error), and the given values in option A are in the correct format for a confidence interval.