An assembly process includes a torque wrench device that automatically tightens compressor housing bolts; the device has a known process standard deviation of ó = 3 lb-ft in the torque applied. A simple random sample of 35 nuts is selected, and the average torque to which they have been tightened is 150 lb-ft. What is the 95% confidence interval for the average torque being applied during the assembly process?
business statistics - PsyDAG, Friday, July 31, 2009 at 10:51am
95% confidence interval is μ ± 1.96 SD.
I hope this helps. Thanks for askng.