Suppose a random variable has population mean
-148 and population standard deviation
37.40. What is the lower and upper values of the
probability interval containing 95% of the sample
means of sample size n = 113?
Lower =
Upper =
Ans:
mean=148
population standard deviation=37.40
n=113
lower=148-1.96*(37.40/sqrt(113))=141.10
upper=148+1.96*(37.40/sqrt(113))=154.90
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