The diameter of steel rods manufactured on two different extrusion investigated. Two random samples of sizes n₁ = 10 and n₁ = 13 are selected, and 0.43 and ₂ the sample means and sample variances are ₁ = 8.93, s 8.82, s2 = 0.30, respectively. Assume that o2 = 2 and that the data are drawn from a normal distribution. (a) Is there evidence to support the claim that the two machines produce rods with different mean diameters? Use a P-value in arriving at this conclusion (b) Construct a 95% CI for the difference in mean rod diameter. Interpret this interval

The following three independent random samples are obtained from three normally distributed populations with equal variance.  The dependent variable is starting hourly wage, and the groups are the types of position (internship, co-op, work study). We are testing the claim that the starting salaries for new college graduate are different depending on the positions at α=0.05α=0.05 given the following data Group 1: Internship Group 2: Co-op Group 3: Work Study 12.5 13.75 12.75 12 14.5 12 9.5 13.25 14 13.5 13 13.5 12 14 12.75 15.5 14.5 11.75 12.25 14.75 10.5 14 14.75 13 13 15.5 13.5 For this study, we should use ----     ?           2. Your friend Vivian helped you with the null and alternative hypotheses...H0: μ1=μ2=μ3H0: μ1=μ2=μ3H1:H1: At least one of the mean is different from the others. 3. The test-statistic for this data = ? (Please show your answer to 3 decimal places.)   4. The p-value for this sample = ?  (Please show your answer to 4 decimal…

You wish to test the following claim (HaHa) at a significance level of α=0.05      Ho:μ1=μ2      Ha:μ1≠μ2You believe both populations are normally distributed, but you do not know the standard deviations for either. However, assume that the variances of the two populations are equal. You obtain a sample of size n1=23 with a mean of ¯x1=74.5 and a standard deviation of SD1=20.4 from the first population. You obtain a sample of size n2=11with a mean of ¯x2=89.8and a standard deviation of SD2=7.3 from the second population.What is the test statistic for this sample? (Report answer accurate to three decimal places.) test statistic = What is the p-value for this sample? (Report answer accurate to four decimal places.) p-value = The p-value is... less than (or equal to) αα greater than αα This test statistic leads to a decision to... reject the null accept the null fail to reject the null As such, the final conclusion is that... There is sufficient evidence to warrant rejection of…

The following three independent random samples are obtained from three normally distributed populations with equal variance.  The dependent variable is starting hourly wage, and the groups are the types of position (internship, co-op, work study). We are testing the claim that the starting salaries for new college graduate are different depending on the positions at α=0.05α=0.05 given the following data Group 1: Internship Group 2: Co-op Group 3: Work Study 10.5 14.25 14.25 12 15.25 8.75 10 15.25 15.75 11 15.75 10.5 16.25 14 9.75 10.75 12.5 15 10.75 14.25 15.75 16.25 13 14.25 12.25 15.5 9.5 8.75 17 12.5 For this study, we should use ???               2. Your friend Valerie helped you with the null and alternative hypotheses...H0: μ1=μ2=μ3H0: μ1=μ2=μ3H1:H1: At least one of the mean is different from the others. 3. The test-statistic for this data = ??? (Please show your answer to 3 decimal places.)   4. The p-value for this sample = ????  (Please show…