Analysis of a random sample consisting of m= 20 specimens of cold-rolled steel to determine yield...
Analysis of a random sample consisting of m = 20 specimens of cold-rolled steel to determine yield strengths resulted in a sample average strength of ¯x = 29.8 ksi. A second random sample of n = 25 two-sided galvanized steel specimens gave a sample average strength of ¯y = 34.7 ksi. Assuming that the two yield-strength distributions are normal with σ1 = 4.0 and σ2 = 5.0.(a) Find the 99% confidence interval of the difference µ1 − µ2 between the...
please help Example 9.3 Analysis of a random sample consisting of m= 20 specimens of cold-rolled steel to determine yield strengths resulted in sample average strength of x = 29.8 ksi. A second random sample of n = 25 two-sided galvanized steel specimens gave a sample average strength of y = 34.7. Assume that the two yield-strength distributions are normal with o, - 4.0 and o, - 5.0 (suggested by a graph in the article "Zinc-Coated Sheet Steel: An Overview".)...
Chapter IU! Hypothesis Testing Exercises (1): A random sample of 6 steel beams has a mean com- pressive strength of 58,392 psi (pounds per square inch) with a standard deviation of 648 psi. Use this information and the level of significance a = 0.05 to test whether the true average compressive strength of the steel from which this sample came is 58,000 psi. Assume normality. Roelve the show verrien ifn-en 5. tereo Head Exercises (2): Studying the flow of traffic...
Can Anyone help me with these 7 questions? Questions: Q1. A random sample has been taken from a normal distribution and the following confidence intervals constructed using the same data: (38.02, 61.98) and (39.95, 60.05) (a) What is the value of the sample mean? (b) One of these intervals is a 95% CI and the other is a 90% CI. Which one is the 95% CI? Why? Q2. A civil engineer is analyzing the compressive strength of concrete. Compressive strength...