Two different hardening processes, (1) saltwater quenching and (2) oil quenching, are used on samples of a particular type of metal alloy. The results are given below:- Saltwater Quench 145 150 153 148 141 152 146 154 139 148 Oil Quench 152 150 147 155 140 146 158 152 151 143 For the above data set calculate the following confidence intervals: (i) 95% confidence interval for the population mean of the saltwater quench. (ii) 95% confidence interval for the population standard deviation for the saltwater quench. (iii) 95% confidence interval for the population ratio of variances (iv) 95% confidence interval for the difference in population means For each confidence interval, interpret the result in the context of the original problem for which the data set was collected.

You may need to use the appropriate appendix table or technology to answer this question. Recall the method used to obtain a confidence interval for the difference between two population means for matched samples. (a) The following data are from matched samples taken from two populations. Compute the difference value for each element. (Use Population 1 - Population 2.) Population Element 12 Difference 1 11 8 2 78 3 9 6 4 12 7 5 13 10 6 15 15 7 15 14 (b) Compute d. (c) Compute the standard deviation s. (Round your answer to two decimal places.) (d) What is the point estimate of the difference between the two population means? (Use Population 1 - Population 2.) (e) Provide a 95% confidence interval for the difference between the two population means. (Use Population 1 - Population 2. Round your answers to two decimal places.) to ☆

Given two independent random samples with the following results: n₂ = 8 x₂ = 124 $2 = 28 = 16 n₁ x₁ = 94 $1 = 16 Use this data to find the 90 % confidence interval for the true difference between the population means. Assume that the population variances are equal and that the two populations are normally distributed. Copy Data Step 1 of 3: Find the point estimate that should be used in constructing the confidence interval.

Wk Qu. 13-11 A simulation returns... A simulation returns the following statistics: Mean 100 Standard Deviation: 5 Mode: 96 Minimum:75 Maximum: 135 Standard Error: 8. What is the most likely value? Most likely value A 68% confidence interval for the true mean would start at a value of 92 and end at a value of 108. A 68% confidence interval for the true mean would start at a value of and end at a value 108