A firm carried out a tensile strength test on its product (metallic rod) before and after alloying. The table below depicts the results: Sample size Sample mean Sample SD Kg/mm² Before Alloying 125 162.25 9.6 After Alloying 125 176.75 7.2 (1 point) Is there sufficient evidence that the true mean of the tensile strength of the metallic rod increased by more than 12 Kg/mm² after alloying at α = 0.05? Hint: VAfter > VBefore (0.5 point) Determine the P-value for this test.
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Alternative hypothesis (Ha): The true mean of the tensile strength of the metallic rod increased by more than 12 Kg/mm after alloying. Show more…
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