SOLUTION: For a psychology experiment, Emma is assigned the task of finding the average number of hours U.S. college students sleep each night. Her results must be at the 99% level of confi

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Question 854370: For a psychology experiment, Emma is assigned the task of finding the average number of hours U.S. college students sleep each night. Her results must be at the 99% level of confidence with a maximum margin of error of 0.1 hours. Assuming the standard deviation is 1.2 hours (based on a previous, reliable study), how many students must Emma survey?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

90%	z =1.645

92%	z = 1.751

95%	z = 1.96

98%	z = 2.326

99%	z = 2.576

Question States***

ME = .1 =  2.576*1.2/sqrt(n) 

     sqrt%28n%29+=+2.576%2A1.2%2F.1

             n = 955.55  0r  956 rounded Up