Six random determinations of sulfur content in steel at a particular point in a process gave the values 3.05, 3.11, 3.14, 3.24, 3.18, and 3.08. Assume the values are normally distributed. A previous study based on a sample of 21 random observations gave an estimate of variance of 1.51 × 10^–3. Use the 5% level of significance. a. Compute for the new sample variance. b. Using the variance ratio, is the variance significantly higher now?

Six random determinations of sulfur content in steel at a particular point in a process gave the values 3.05, 3.11, 3.14, 3.24, 3.18, and 3.08. Assume the values are normally distributed. A previous study based on a sample of 21 random observations gave an estimate of variance of 1.51 × 10^–3. Use the 5% level of significance. a. Compute for the new sample variance. b. Using the variance ratio, is the variance significantly higher now?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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