Business Statistics Exam 1 Practice This practice exam is provided as an aid for preparing for the exam. It is recommended that you answer these questions after you have studied to identify areas where you may need additional study time. The questions are not necessarily reflective of the type or number of questions you will see on the actual exam. 1. For each of the following variables, determine whether it is qualitative or quantitative. Then, identify the appropriate measurement scale for each variable. Variable Qualitative or Quantitative Measurement Scale Academic major Time spent studying (in hours) Classification (FR, SO, JR, SR) SAT score 2. According to the Census Bureau, the 2009 United States median household income was $49,777 with a mean household income of $67,976. What does this tell you about the shape of the distribution of household income in the United States? 3. Use the following sample data: 44 41 51 40 26 44 39 35 a. Determine the mean. b. Determine the median. c. Determine the mode. d. Determine the variance. e. Determine the standard deviation 4. The following data represent highway fuel consumption in miles per gallon for a random sample of 55 models of passenger cars. 30 27 22 25 24 25 24 15 35 35 33 52 49 10 27 18 20 23 24 25 30 24 24 24 18 20 25 27 24 32 29 27 24 27 26 25 24 28 33 30 13 13 21 28 37 35 32 33 29 31 28 28 25 29 31 a. Construct a frequency distribution using five classes (round the approximate class width to the next highest integer) Class Limits Frequency b. Construct a relative frequency distribution using the same five classes as in part a. Class Limits Relative Frequency c. Draw a histogram for these data using the frequency distribution you constructed in part a. 5. If a data set has a mean equal to 4,750 with a standard deviation equal to 687, is the value 6,831 an outlier? 6. Consider the following set of sample data. X Y 13 36 6 20 8 31 3 8 10 25 a. Draw a scatter diagram to illustrate the relationship between X and Y. b. Compute the sample covariance. c. Compute the correlation coefficient. Does this value agree with the relationship you observed in part a? Explain.