(Just answers)
1.
Lower bound is:
Upper bound is:
The manufacturer of hardness testing equipment uses steel-ball indenters to penetrate metal that is being tested. However, the manufacturer thinks it would be better to use a diamond indenter so that all types of metal can be tested. Because of differences between the two types of indenters, it is suspected that the two methods will produce different hardness readings. The metal specimens to be tested are large enough so that two indentions can be made. Therefore, the manufacturer uses both indenters on each specimen and compares the hardness readings. Construct a 95% confidence interval to judge whether the two indenters result in different measurements . X Note: A normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers. i Data Table Click the icon to view the data table. Construct a 95% confidence interval to judge whether the two indenters result in different measurements, where the differences are computed as 'diamond minus steel ball'. Specimen 1 3 4 5 6 7 8 9 The lower bound is 2 Steel ball 50 57 61 70 68 54 65 51 53 The upper bound is 52 56 61 74 69 56 68 51 Diamond 56 (Round to the nearest tenth as needed.) Print DoneTo illustrate the effects of driving under the influence (DUI) of alcohol, a police officer brought a DUI simulator to a local high school. Student reaction time in an emergency was measured with unimpaired vision and also while wearing a pair of special goggles to simulate the effects of alcohol on vision. For a random sample of nine teenagers, the time (in seconds) required to bring the vehicle to a stop from a speed of 60 miles per hour was recorded. Complete parts (a) and (b). Note: A normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers. Click the icon to view the data table. i Data Table X (a) Whether the student had unimpaired vision or wore goggles first was randomly selected. Why is this a good idea in designing the experiment? A. This is a good idea in designing the experiment because it controls for any "learning" that may occur in using the simulator. O B. This is a good idea in designing the experiment because the sample size is not large enough. Subject 2 3 4 5 6 7 8 9 O C. This is a good idea in designing the experiment because reaction times are different. Normal, X; 4.49 4.34 4.58 4.65 4.31 4.80 4.55 5.00 4.79 Impaired, Y; 5.86 5.67 5.45 5.29 5.83 5.49 5.23 5.63 5.63 (b) Use a 95% confidence interval to test if there is a difference in braking time with impaired vision and normal vision where the differences are computed as "impaired minus normal." The lower bound is The upper bound is Print Done (Round to the nearest thousandth as needed.)To test the belief that sons are taller than their fathers, a student randomly selects 13 fathers who have adult male children. She records the height of both the father and son in inches and obtains the following data. Are sons taller than their fathers? Use the a = 0.025 level of significance. Note: A normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers. Click the icon to view the table of data. i Table of height data X OE. The sample size must be large. Let dj = X; - Yj. Write the hypotheses for the test. Height of Height of Ho: Hd = 0 Father, X Son, Yi H1 : Hd
