An experiment was conducted to determine the abrasion resistance of a new type of automobile paint. Twelve different strips of metal were painted with the new paint. The abrasion resistance of each piece was then tested on a machine. In the sample, the abrasion resistance values ranged from 2.1 units to 4.3 units.
1. What is the parameter of interest in this study?
2. What are the two assumptions required for constructing a confidence interval for the population mean in this case?
3. The Q-Q plot for these data is shown. What assumption is this plot used to assess? Based on this plot, do we have evidence that the assumption holds? Why or why not?
4. The sample mean resistance is 3.2 and the standard deviation is 0.73. Which distribution will be used to construct a 95% CI for the population mean? BE SPECIFIC
5. The sample mean resistance is 3.2 and the standard deviation is 0.73. What is the 95% CI for the population mean resistance value?
6. Which of the following is the correct interpretation of the 95% confidence level?(
1 answer