Common last names. The U.S. Census Bureau says that the 10 most common names in the United States are (in order) Smith, Johnson, Williams, Brown, Jones, Miller, Davis, Garcia, Rodriguez, and Wilson.24 These names account for 4.9% of all U.S. residents. Out of curiosity, you look at the authors of the textbooks for your current courses. There are 12 authors in all. Would you be surprised if none of the names of these authors were among the 10 most common? Give a probability to support your answer and explain the reasoning behind your calculation.
Chapter - 9 Two-Sample Problems Sec - 9.1 & 9.2 Comparison of Two Population Means Suppose we wish to compare the average income of all adults in one region of the country with the average income of those in another region Independent and Dependent Samples: Two samples are independent if the sample selected from one population is not related to the sample selected from the second population. Two samples are dependent if each member of one sample corresponds to a member of the other sample. Dependent samples are also called paired samples or matched samples. Example 1: Consider a drug company that wants to test the e▯ectiveness of a new drug in reducing blood pressure. They could collect data in two ways: 1) Sample the blood pressures of the sam