SOLUTION: Assume that a sample is used to estimate a population mean μ μ . Find the 90% confidence interval for a sample of size 67 with a mean of 42.3 and a standard deviation of 14

Algebra ->  Probability-and-statistics -> SOLUTION: Assume that a sample is used to estimate a population mean μ μ . Find the 90% confidence interval for a sample of size 67 with a mean of 42.3 and a standard deviation of 14      Log On


   



Question 1198519: Assume that a sample is used to estimate a population mean
μ
μ
. Find the 90% confidence interval for a sample of size 67 with a mean of 42.3 and a standard deviation of 14.1. Enter your answer as an open-interval (i.e., parentheses) accurate to 3 decimal places.
90% C.I. =
Answer should be obtained without any preliminary rounding.

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

ME+=+z%2Asigma%2Fsqrt%28n%29    = ME+=+1.645%2A14.1%2Fsqrt%2867%29 = 2.837 ( accurate to 3 decimal places)
42.3-2.837 < mu < 42.3 + 2.837
CI(39.463, 45.137)


 = CI	z = value
90%	z =1.645
92%	z = 1.751
95%	z = 1.96
98%	z = 2.326
99%	z = 2.576