16. A steel pipe fittings company claims that the yield strength of its non-tempered couplings is more variable than that of its tempered couplings. A random sample of nine tempered couplings has a standard deviation of 13.1 mega-pascals, and a similar sample of nine non-tempered couplings has a standard deviation of 25.4 mega-pascals. From past data, it is known that the company's production process results in normally distributed yield strengths. Test the company's claim at a = 0.05.© BrainMass Inc. brainmass.com June 3, 2020, 11:19 pm ad1c9bdddf
The expert examines the test claim for steel pipe fittings. A complete, neat and step-by-step solution is provided in the attached Excel file.