5. A materials scientist is working to improve the Ultimate Tensile Strength (UTS) in steel. Suppose 10 batches of the new formulated steel are tested for UTS with the following results (in ksi). Ultimate Tensile Strength (UTS), ksi 76.0 76.3 76.3 76.0 75.8 75.9 76.1 76.2 76.6 76.1 Determine the 98% confidence interval for the mean UTS of the new formulation. [7 marks]
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To calculate the sample mean, we sum up all the values and divide by the number of values. Sample mean = (76.0 + 76.3 + 76.3 + 76.0 + 75.8 + 75.9 + 76.1 + 76.2 + 76.6 + 76.1) / 10 = 76.03 Show more…
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