SOLUTION: find the sample size necessary to estimate the mean weight of all supermodels so that there is 95% confidence that the sample mean is in error by no more than 2 lb. assume that a

Question 852820: find the sample size necessary to estimate the mean weight of all supermodels so that there is 95% confidence that the sample mean is in error by no more than 2 lb. assume that a pilot study suggests that the weights of all supermodels have a std dev of 7.5 lbs
weights of models - 125/127/119/105/128/123/125/110/119/103
Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!

 

Hi,

 = C	z = 1.28155

90%	z =1.645

92%	z = 1.751

95%	z = 1.96

98%	z = 2.326

99%	z = 2.576

ME = 1.96*7.5/sqrt(n) < 2,  n = 54.0225   0r   55 rounded Up

sample size necessary is 55



 

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