1. x̄ = 85 and σ = 8, and n = 64, set up a 95% confidence interval estimate of the population mean μ. Z= 1-(0.05/2) = 1.96 Sample mean= x-bar = 85 Z*s/sqrt(n) = (1.96*8)/sqrt(64) = 1.96 CI= 85 – 1.96= 83.04 CI= 85- 1.96= 86.96 (83.04, 86.96) 2. If x̄ = 125, σ = 24 and n = 36, set up a 99% confidence interval estimate of the population mean μ. Z= 1- (0.01/2) = 0.995= 2.57 Z*s/sqrt(n) = 125 - (2.57*8/sqrt(36) = 3.42-125= 121.58 Z*s/sqrt(n) = 125 + (2.57*8/sqrt(36) = 3.42+125= 128.42 3. The manager of a supply store wants to estimate the actual amount of paint contained in 1-gallon cans purchased from a nationally known manufacturer. It is known from the manufacturer's specification sheet that standard deviation of the amount of paint is equal to 0.02 gallon. A Random sample of 50 cans is selected and the sample mean amount of paint per 1 gallon is 0.99 gallon. 3a. Set up a 99% confidence inter...
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