Understanding Basic Statistics 6th Edition by Charles Henry Brase,Corrinne Pellillo Brase

Exercise 71

Critical Thinking Consider an x distribution with standard deviation = 12.
(a) If specifications for a research project require the standard error of the corresponding
distribution to be 2, how large does the sample size need to be
(b) If specifications for a research project require the standard error of the corresponding
distribution to be 1, how large does the sample size need to be