1. In a statistics class with 136 students, the professor records how much money each

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1 so shows the data collected. student has in his or her possession during the first class of the semester. The histogram 1. In a statistics class with 136 students, the professor records how much money each Page 1 E) Amounts awarded by civil court juries. poor scores but a few do very well. D) The scores of students (out of 100 points) on a very difficult exam in which most get C) The prices of homes in a large city. nearly perfect scores but a few do very poorly. B) The scores of students (out of 100 points) on a very easy exam in which most get A) The salaries of all National Football League players. 3. Which of the following is likely to have a mean that is smaller than the median? E) be determined from the information given. Cannot D) B) 35. C) 375 A) enters the room. The mean age of the five people now in the room is 2 The mean age of four people in a room is 30 years A new person whose age is 55 years E) it is impossible to compare the mean and median for these dat& D) The difference between the man and the media is reduced by the outher C) The mean and median are approximately equal. B) The mean is much smaller than the median A) The mean is much larger than the median. From the histogram, which of the following is true? Amount of Money I I I I I I C.) C) 3 40

2 4. A set of data has a mean that is much larger than the median. Which of the following statements is most consistent with this information? A) A histogram of the data is smetric. B) A histogram of the data is skewed left. C) A histogram of the data is skewed right D) A histogram of the data is bimodal. E) The data set probably has a few low outliers. 5. The median age of five people in a meeting is 30 years. One of the people, whose age is 50 years, leaves the room. The median age of the remaining four people in the room is A) 40 years. B) 30 years. C) 25 years. D) less than 30 years. E) Cannot be determined from the information given. 6. The average salary of all female workers is $35,000. The average salary of all male workers is $41,000. What must be true about the average salary of all workers? A) It must be $38,000. B) It must be larger than the median salary. C) It could be any number between $35,000 and $41,000. D) It must be larger than $3 8,000. E) It cannot be larger than $40,000. Page 2

3 7. The following bar graph gives the percent of owners of three brands of trucks who are satisfied with their truck. 97%-. a, (I) c (13.J.J1O C a, C.) a) 0 95%- FORD CHEVLLET I..J1A From this graph we may legitimately conclude A) there is veiy little difference in the satisfaction of owners for the three brands. B) Chevrolet owners are substantially more satisfied than Ford or Toyota owners. C) owners of other brands of trucks are less satisfied than the owners of these three brands. D) Chevrolet probably sells more trucks than Ford or Toyota. E) a pie chart would have been a better choice for displaying this data. 8. The standard deviation of 16 measurements of peoples weights (in pounds) is computed to be 5.4. The variance of these measurements is A) B) D) 256. E) Page 3

4 Use the following to answer question 9: During the early part of the 1994 baseball season, many sports fans and baseball players noticed that the number of home runs being hit seemed to be unusually large. Below are separate stemplots for the number of home runs by American and National League teams. American League National League J J j 9. Which of the following is a correct statement? A) The American League plot is reasonably symmetric. B) The National League plot is slightly skewed to the left. C) The median number of home runs hit by American League teams was higher than the median number hit by National League teams. D) The mean number of home runs hit by American League teams was more than 6 higher than the mean for National League teams. E) Allof the above. 10. A particularly common question in the study of wildlife behavior involves observing contests between residents of a particular area and intruders. In each contest, the residents either win or lose the encounter (assuming there are no ties). Observers might record several variables, listed below. Which of these variables is categorical? A) The duration of the contest (in seconds). B) The number of animals involved in the contest. C) Whether the residents win or lose. D) The total number of contests won by the residents. E) None of these. Page 4

5 Use the following to answer question 11: Page 5 A) have a separate c ass interval for each observation to get the most informative plot. B) make sure the heights of the bars exceed the widths of the class intervals so that the E) scale the vertical axis according to the variable whose distribution you are displaying. 1)) leave large gaps between bars. This allows room for comments. bars are true rectangles. interval. C) label the vertical axis so the reader can determine the counts or percent in each class 13. When drawing a histogram it is important to C) It could be any number between 19 and 21. E) Itmustbeover2l. A) It must be 20. D) Itmustbe2l. B) It must be What Is true abut the median age? Number of students Age The ages of people in a class (to the nearest year) are as follows: B) D) E) 137. C) 133. A) The median point total for this class is The point totals for the 10 students are given in the stemplot below. ror a physics course containing 10 students, the maximum point total for the quarter was 200.

6 14. A sample of production records for an automobile manufacturer shows the following figures for production per shift: The variance of the above data is A) B) C) D) E) 20,00. Use the following to answer question 15: A sample was taken of the salaries of 20 employees of a large company. The following boxplot shows the salaries (in thousands of dollars) for this year. 70 cr2 so Based on the boxplot, which of the following statements is true? A) The maximum salary is between $60,000 and $70,000. B) The minimum salary is $20,000. C) The range of the middle half of the salaries is about $20,000. 1)) The median salary is about $40,000. E) 25% of the employees make more than $70,000. Page 6

7 Use the following to answer questions 16-17: A sample was taken of the salaries of 20 employees of a large company. The following are the salaries (in thousands of dollars) for this year. For convenience, the data are ordered Suppose each employee in the company receives a $3,000 raise for next year (each employe&s salary is increased by $3,000). 16. The standard deviation of the salaries for the employees will A) be unchanged. B) increase by $3,000. C) be multiplied by $3,000. D) increase by -i$3,000 E) decrease by $3, , The mean salary for the employees will A) be unchanged. B) increase by $3,000. C) be multiplied by $3,000. D) increase by /ooo. E) increase by $150. Page 7

8 Use the following to answer questions 18-19: The timeplot below gives the number of burglaries committed each month for a city in Ohio. The plot is for the three-year period January 1987 December I I I Jan, 1987 Jin, 1988 Jan The maximum number of burglaries for a month in 1988 was about A) 20. B) 25. C) 30. D) 33. E) Which of the following is a true statement? A) The number of burglaries in each month of 1988 were lower than the number of burglaries in each month of B) The median number of burglaries for a month in 1988 was a little over 2. C) The total number of burglaries in 1989 was higher than in D) None of the above. E) More burglaries seem to be commited in June, July, and August during 1987, 1988, and Page 8

9 4 5 but not the right. Page 9 are some of the variables from a survey conducted by the U S Postal Service Which of D) Age of respondent E) Number of rooms in the dwelling C) Total household income, before taxes, in 1993 B) Number of people, both adults and children, living in the household A) County of residence the variables is categorical? 21 A survey typically records many variables of interest to the researchers involved Below D) 16% C) 12% B)4% A)3% What percent of the schools have an acceptance rate of under 20%? Acceptance Rate C.) C.) C-) among 25 business schools in In each class interval, the left endpoint is included 20. The following histogram represents the distribution of acceptance rates (percent accepted)

10 Use the following to answer question 22: A sample was taken shows the salaries (in thousands of the salaries of 20 employees of a large company. The following boxplot of dollars) for this year Cl2 o Based on the boxplot, the five-number summary is A) 28, 39, 48, 60.5, 77. B) 28, 58, 77. C) 51, 58, 77. D) E) 26, 39, 48, 60.5, ,48, 28,39, 28,41,51,60.5, There are three children in a room, ages three, four, and five. enters the room the A) mean age will stay the same but the variance will increase. B) mean age will stay the same but the variance will decrease. C) mean age and variance will stay the same. D) mean age and variance will increase. E) mean age and variance will decrease. If a four-year-old child 24. Lf your score on a test is at the 60th percentile, you A) below the lower quartile. B) between the lower quartile and the median. C) between the median and the upper quartile. D) above the upper quartile. E) Can t say where it lies relative to the quartiles. know that your score lies Page 10