Test claim for steel pipe

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Reference no: EM13110440

A steel pipe fittings company claims that the yield strength of its nontempered couplings is more variable than that of its tempered couplings. A random sample of nine tempered couplings has a standard deviation of 13.1 megapascals, and a similar sample of nine nontempered couplings has a standard deviation of 25.4 megapascals. 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.

Reference no: EM13110440

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