Question 1 of 20 1.0 Points A sample of 20 observations has a standard deviation of 4. The sum o ...
Question 1 of 20 1.0 Points A sample of 20 observations has a standard deviation of 4. The sum of the squared deviations from the sample mean is: A. 320 B. 304 C. 288 D. 400 Reset Selection Question 2 of 20 1.0 Points Suppose that a histogram of a data set is approximately symmetric and "bell shaped". Approximately, what percent of the observations are within three standard deviations of the mean? A. 50% B. 99.7% C. 95% D. 68% Reset Selection Question 3 of 20 1.0 Points Which of the following correctly describes the relationship between a sample and a population? A. A sample is a group of populations that are subject to observation. B. A population and a sample are not related. C. A population is a group of samples that may or may not be included in a study D. A sample is a group of subjects selected from a population to be studied. Reset Selection Question 4 of 20 1.0 Points A histogram that has a single peak and looks approximately the same to the left and right of the peak is called: A. bimodal B. symmetric C. proportional D. balanced Reset Selection Question 5 of 20 1.0 Points Which of the following statements is true for the following data values: 7, 5, 6, 4, 7, 8, and 12? A. Only the mean and median are equal B. The mean, median and mode are all equal C. Only the median and mode are equal D. Only the mean and mode are equal Reset Selection Question 6 of 20 1.0 Points If a variable has possible values –2, 6, and 17, then this variable is A. both a continuous and a discrete variable B. a discrete variable C. neither a continuous nor a discrete variable D. a continuous variable Reset Selection Question 7 of 20 1.0 Points Which of the following statements is true regarding the data set 10, 10, 10, 10, and 10? A. The range is zero B. The standard deviation equals zero C. The interquartile range equals zero D. all of the above Reset Selection Question 8 of 20 1.0 Points Gender and State are examples of which type of data? A. Discrete data B. Continuous data C. Categorical data D. Ordinal data Reset Selection Question 9 of 20 1.0 Points If a value represents the 95th percentile, this means that A. 95% of the time you will observe this value B. 95% of all values are below this value C. 95% of all values are above this value D. there is a 5% chance that this value is incorrect Reset Selection Question 10 of 20 1.0 Points A scatter plot would be useful for A. Showing the trend of sales, over time, of five different brands of blank DVDs B. Showing the relationship between the sales of blank CDs and blank DVDs C. Showing the top selling brands of blank DVDs D. Showing the relative number of sales of four different brands of blank DVDs Reset Selection Question 11 of 20 1.0 Points Which of the following indicates how many observations fall into various categories? A. The frequency table B. The tabulation scale C. The Likert scale D. The sample table Reset Selection Question 12 of 20 1.0 Points Which of the following are the three most common measures of central location? A. Mean, median, and standard deviation B. Mean, median, and mode C. Mean, variance, and standard deviation D. Mean, median, and variance Reset Selection Part 2 of 3 - Question 13 of 20 1.0 Points Click to see additional instructions A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result. Did Well in Exam Did Poorly in Exam Studying for Exam 60 15 Went Partying 22 53 Question 14 of 20 1.0 Points Click to see additional instructions The following data are the base salaries, in thousands of dollars, of 50 chief executive officers for a sample of companies doing business with the state of Connecticut. That is, the first entry in the table below corresponds to a salary of $125,000. A copy of this data set can be found in the Excel Workbook called CEOSalaries.xls. 125 157 113 127 201 165 145 119 148 158 148 168 117 105 136 136 125 148 108 178 179 191 225 204 104 205 197 119 209 157 209 205 221 178 247 235 217 222 224 187 265 148 165 228 239 245 152 148 115 150 Find the median of the CEO salaries, in thousands of dollars, rounded to 2 decimal places. Do not use a dollar sign. Note: $177,760 should be recorded as 177.76. Question 15 of 20 1.0 Points Click to see additional instructions Question 16 of 20 1.0 Points Click to see additional instructions The following data are the base salaries, in thousands of dollars, of 50 chief executive officers for a sample of companies doing business with the state of Connecticut. That is, the first entry in the table below corresponds to a salary of $125,000. A copy of this data set can be found in the Excel Workbook called CEOSalaries.xls. 125 157 113 127 201 165 145 119 148 158 148 168 117 105 136 136 125 148 108 178 179 191 225 204 104 205 197 119 209 157 209 205 221 178 247 235 217 222 224 187 265 148 165 228 239 245 152 148 115 150 Find the interquartile range of the CEO salaries, in thousands of dollars, rounded to 2 decimal places. Do not use a dollar sign. Note: $177,760 should be recorded as 177.76. Question 17 of 20 1.0 Points Click to see additional instructions A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result. Did Well in Exam Did Poorly in Exam Studying for Exam 60 15 Went Partying 22 53 Question 18 of 20 1.0 Points Click to see additional instructions A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result. Did Well on Exam Did Poorly on Exam Studying for Exam 60 15 Went Partying 22 53 If the sample is a good representation of the population, what percentage of those who did poorly on the final exam should we expect to have spent the weekend studying? Place your answer in the blank, rounded to 2 decimal places. Do not use a percentage sign (%). For example, 44.44 would be a legitmate answer. Part 3 of 3 - Question 19 of 20 1.0 Points A histogram is skewed to the left (or negatively skewed) if it has a single peak and the values of the distribution extend much further to the right of the peak than to the left of the peak. Reset Selection Question 20 of 20 1.0 Points If you are in a class where most students do reasonably well on a test but a few pull down the class average, the histogram describing the test scores will indicate a positively-skewed distribution. Reset Selection
