BUS/ST 350 ReilandEXAM 1 Practice ProblemsMaterial covered: Course Pack: Lecture Unit 1, Lecture Unit 2, Lecture Unit 3WARNING: these practice problems may not cover all the material for which you are responsible! 1. The heights of American men aged 18 to 24 are approximately symmetric and mound shaped with mean 68 inches and standard deviation 2.5 inches. Half of all young men are shorter than a) 65.5 inches b) 68 inches c) 70.5 inches d) can't tell because the median height is not given 2. Use the information in Problem 1. What percent of young men are taller than 6' 1" ? a) 94.5% b) 44.5% c) 5.5% d) 2.5%3. A Consumer Reports article on energy bars gave the brand name, flavor, price, number of calories, andgrams of protein and fat. Describe the Who, What, Why, Where, When, How. What variables arecategorical? What variables are quantitative?4. Suppose for a set of data we calculate ( 4.51, then the standardBßBßÞÞÞßB B"# ( 33œ"8!B œ) # deviation is a) .75 b) .87 c) .64 d) .80 e) none of the above5. A standardized test designed to measure math anxiety has a mean of 100 and a standard deviationof 10 in the population of first year college students. Which of the following observations wouldyou suspect is an outlier? a) 150 b) 100 c) 90 d) all of the above e) none of the above6. Which of the following best describes a risk in using the sample range to measure spread?Choose one of the following:a) The statistic is not in the same unit of measurement as the observations themselves.b) The largest or smallest observation may be a mistake or an outlier. c) It is complicated to compute, which may result in an error. d) It always produces spreads that are too large. 7. The following 2-way table shows students by major and home state for a small private school in thenortheast U.S. Major Program of Study Biology Accounting History EducationPA 80 65 55 100NJ 50 40 65 95NY 75 50 45 80MD 65 55 40 40Home State a. Find the marginal distribution for home state.b. Find the conditional distribution (in percentages) of major distribution for the home state of NJ.c. Find the conditional distribution (in percentages) of home state distribution for the biology major.8. Twenty-eight applicants interested in working for the Food Stamp program took an examination designed tomeasure their aptitude for social work. The following test scores were obtained:79, 93, 84, 86, 77, 63, 46, 97, 87, 88, 87, 92, 68, 72, 86, 98, 81, 70, 66, 98, 59, 76, 68, 91, 94, 85, 88, 79.a. Find . U"b. Construct a boxplot for these observations. Do you observe any outliers?9. Two students are enrolled in an introductory statistics course at the University of Florida. The first studentis in a morning section and the second student is in an afternoon section. If the student in the morningBUS/ST 350 page 2Practice Problems Exam 1section takes a midterm and earns a score of 76, while the student in the afternoon section takes a midtermwith a score of 72, which student has performed better compared to the rest of the students in his respectiveclass? For the morning class, the class mean was 64 with a standard deviation of 8. For the afternoon class,the class mean was 60 with a standard deviation of 7.5.10. Raw scores on evaluation tests given to elementary school children are often transformed for easiercomparison. A test of reading ability has mean 72 and standard deviation 25 when given to third graders.So that we can compare third grade scores with “normed” scores of students in other grades, we want scoresin the third grade to have mean 100 and standard deviation 20. a. What linear transformation will change third grade scores into new scores = that have theBB+,B8/Adesired mean and standard deviation? (Use to preserve the order of the scores).,! b. Nancy is a third grade student who scored 75 on the test. Find Nancy's transformed score.11. Which of the following describes a basic DIFFERENCE between nominal data and ordinal data? a. Nominal and ordinal data are both quantitative data. b. Nominal and ordinal data are both qualitative data. c. Nominal data are qualitative data whereas ordinal data are quantitative data. d. Nominal data have a meaningful zero point and the ratio of the two data values is meaningfulwhereas with ordinal data the zero point is arbitrary. e. Nominal data classify items into one of a set of categories whereas ordinal data classify itemsinto categories that can be ranked and ordered.12. In the stem and leaf plot below the stems are the one's digit and the leaves are the first digit to the right of thedecimal point, so 2 | 1 denotes the value 2.12 | 1 1 2 5 8 93 | 3 4 5 84 | 2 2 4 55 | 1 56 | 1 57 | 88 | 1a. Is the data right-skewed or left-skewed?b. What is the median?c. What is ?U$13. A manufacturer of computer hard disk drives knows that its computer hard disk drives have amean time to failure of 24 months with a standard deviation of 4 months. The failure data is known to besymmetric and mound-shaped. Determine the following: a. What is the approximate proportion of the manufacturer's hard drives that will fail laterthan 16 months? b. What is the approximate proportion of the manufacturer's hard drives that will fail between 16 monthsand 28 months? c. If the manufacturer offers a 20 month warranty on its hard drive, what is the approximateproportion of these hard drives that could fail under warranty?14. The following data are a sample of the percentage rates of return experienced by six-month Eurodollardeposit purchasers:1 2 2 1 1 4 2 3 1The standard deviation is: a. 4 b. 2 c. 1.05 d. 1.11 e. can't be done since some values are negativeBUS/ST 350 page 3Practice Problems Exam 1 Consider the following histograms of variables labeled X1, X2 and X3:15. The median for variable X2 would be around a. 10 b. 305 c. 250 d. impossible to tell16. The third quartile for variable X1 would be around a. 12 b. 8 c. 5 d. 1517. The distribution in which the mean and median are most different would be a. X1 b. X2 c. X3 d. It is impossible to tell.18. The standard deviation for variable X1 would be a. About the same as the standard deviation for variable X2. b. Smaller than the standard deviation for variable X2. c. Larger than the standard deviation for variable X2. d. It is