Question

The Ball Corporation's beverage can manufacturing plant in Fort Atkinson, Wisconsin, uses a metal supplier that provides metal with a known thickness standard deviation σ = .000631 mm. Assume a random sample of 46 sheets of metal resulted in an x bar = .3293 mm.

Calculate the 90 percent confidence interval for the true mean metal thickness. (Round your answers to 4 decimal places.)
  
The 90% confidence interval is from   to   

Answer 1