Exam Name___________________________________ MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Determine whether the underlined value is a parameter or a statistic. 1) In a survey conducted in the town of Atherton, 2 2% of adult respondents reported that they had been involved in at least one car accident in the past ten years. 1) _____ A) statistic B) parameter Provide an appropriate response. 2) A medical journal published the results of an experiment on anorexia. The experiment investigated the effects of a controversial new therapy for anorexia. Researchers measured the anorexia levels of 83 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's anorexia levels. The differences between the the pre- and post-therapy anorexia levels were reported. What type of experimental design is this? 2) _____ A) randomized block design C) matched-pairs design B) single-blind design D) completely randomized design 3) A medical journal published the results of an experiment on anorexia. The experiment investigated the effects of a controversial new therapy for anorexia. Researchers measured the anorexia levels of 62 adult women who suffer moderate conditions of the disorder. After the therapy, the researchers again measured the women's anorexia levels. The differences between the the have in this experiment? and 3) _____ anorexia levels were reported. How many levels does the treatment A) 1 (therapy) B) 62 (the adult women who suffer from anorexia) C) 2 (pre- and post-therapy) D) 124 (the adult women who suffer from anorexia measured pre- and post-therapy) Determine the sampling technique which is used. 4) An education researcher randomly selects 25 of the nation's junior colleges and interviews all of the professors at each school. What sampling technique was used? 4) _____ A) random B) systematic C) convenience D) stratified E) cluster Describe the shape of the distribution. 5) 5) _____ A) skewed to the right B) skewed to the left C) bell shaped D) uniform Provide an appropriate response. 6) Retailers are always interested in determining why a customer selected their store to make a purchase. A sporting goods retailer conducted a customer survey to determine why its customers shopped at the store. The results are shown below. What percentage of the customers responded that the merchandise was the reason they shopped at the store? 6) _____ A) 30% B) 43% C) 29% D) 50% 7) The number of students enrolled in a physics class for the last ten semesters are listed below. Find the median number of students. 7) _____ A) 70 students B) 66 students C) 67 students D) 68 students 8) Which measure of central tendency is more representative of the typical observation if the graph of the data is skewed to the right? 8) _____ A) Mode B) Mean C) Midrange D) Median 9) Last year batting averages in professional baseball averaged 0. 263 with a high of and a low of 250 at-bats). Based on this information, which measure of variation could be calculated? 9) _____ A) range C) percentile (minimum B) variance D) standard deviation 10) Fill in the blank. ____________ gives us a method of interpreting the standard deviation that applies to any data set, regardless of the shape of the distribution. 10) _____ A) Chebyshev's rule and the empirical rule B) Chebyshev's rule C) The Empirical Rule D) none of these 11) An Excel printout of some descriptive statistics for a set of data is shown below. What is the IQR? 11) _____ A) 15.5 B) 38 C) 15 D) 5.5 Compute the range for the set of data. 12) 0.184, 0.115, 0.457, 0.404, 0.649, 0.294 12) _____ A) 0.351 B) 0.649 C) 0.115 D) 0.534 Provide an appropriate response. 13) Is there a relationship between the raises administrators at State University receive and their performance on the job? A faculty group wants to determine whether job rating (x) is a useful linear predictor of raise (y). Consequently, the group considered the straight-line regression model, the following prediction equation, Using the method of least squares, the faculty group obtained Interpret the estimated slope of the line. 13) _____ A) For a $1 increase in an administrator's raise, we estimate the administrator's rating to decrease 2,000 points. B) For a 1-point increase in an administrator's rating, we estimate the administrator's raise to decrease $2,000. C) For an administrator with a rating of 1.0, we estimate his/her raise to be $2,000. D) For a 1-point increase in an administrator's rating, we estimate the administrator's raise to increase $2,000. Make a scatter diagram for the data. Use the scatter diagram to describe how, if at all, the variables are related. 14) 14) _____ A) The variables appear to be positively, linearly related. B) The variables do not appear to be linearly related. C) The variables do not appear to be linearly related. D) The variables appear to be negatively, linearly related. Provide an appropriate response. 15) The regression line for the given data is = 82. = -2.75x + 96.14. Determine the residual of a data point for which x = 4 and y 15) _____ A) 133.36 B) 85.14 C) 167.14 D) -3.14 Make a scatter diagram for the data. Use the scatter diagram to describe how, if at all, the variables are related. 16) 16) _____ A) The variables do not appear to be linearly related. B) The variables do not appear to be linearly related. C) The variables appear to be negatively, linearly related. D) The variables appear to be positively, linearly related. Provide an appropriate response. 17) The regression line for the given data is y = 145. = 1.488x + 60.46. Determine the residual of a data point for which x = 53 and 17) _____ A) 284.324 B) 5.676 C) -223.22 D) 139.324 Provide an appropriate response. Express your answer as a simplified fraction unless otherwise noted. 18) The manager of a used car lot took inventory of the automobiles on his lot and constructed the following table based on the age of his car and its make (foreign or domestic). A car was randomly selected from the lot. Given that the car selected was a domestic car, what is the probability that it was older than 2 years? Age of Car (in years) 18) _____ A) B) C) D) Provide an appropriate response. 19) A(n) _______________ of a probability experiment is the collection of all outcomes possible. A) Prediction set B) Sample space C) Bernoulli space D) Event set 19) _____ 20) The chart shows the probability of a certain disease for men by age. What is the probability that a randomly selected man between the ages of 35 and 64 has the disease? 20) _____ A) 0.42 B) 0.95 C) 0.14 D) 0.58 21) In a 1-pond bag of skittles the possible colors were red, green, yellow, orange, and purple. The probability of drawing a particular color from that bag is given below. Is this a probability model? Answer Yes or No. Color Red Green Orange Yellow Purple Probability 0.2299 0.1908 0.2168 0.1889 0.1816 21) _____ A) Yes B) No 22) To win at LOTTO in a certain state, one must correctly select 6 numbers from a collection of 51 numbers through 51.) The order in which the selections is made does not matter. How many different selections are possible? 22) _____ A) 18,009,460 B) 720 C) 306 D) 15,890,700 23) According to government data, the probability that an adult was never in a museum is 15%. In a random survey of 10 adults, what is the probability that at least eight were in a museum? 23) _____ A) 0.002 B) 0.200 C) 0.800 D) 0.820 24) Assume that male and female births are equally likely and that the birth of any child does not affect the probability of the gender of any other children. Find the probability of at most three girls in ten births. 24) _____ A) 0.003 B) 0.333 C) 0.172 D) 0.300 25) A quiz consists of 10 true or false questions. To pass the quiz a student must answer at least eight questions correctly. If the student guesses on each question, what is the probability that the student will pass the quiz? 25) _____ A) 0.055 B) 0.20 C) 0.8 D) 0.08 Classify the following random variable according to whether it is discrete or continuous. 26) the number of bottles of juice sold in a cafeteria during lunch 26) _____ A) discrete B) continuous Provide an appropriate response. 27) A brewery has a beer dispensing machine that dispenses beer into the company's 12 ounce bottles. The distribution for the amount of beer dispensed by the machine follows a normal distribution with a standard deviation of 0.11 ounce. The company can control the mean amount of beer dispensed by the machine. What value of the mean should the company use if it wants to guarantee that 98.5% of the bottles contain at least 12 ounces (the amount on the label)? 27) _____ A) 12.001 oz B) 12.002 oz C) 12.239 oz D) 12.267 oz 28) Suppose a brewery has a filling machine that fills 12 ounce bottles of beer. It is known that the amount of beer poured by this filling machine follows a normal distribution with a mean of Find the probability that the bottle contains fewer than A) 0.4938 B) 0.0062 C) 0.5062 and a standard deviation of 0.04 ounce. of beer. 28) _____ D) 0.9938 29) The length of time it takes college students to find a parking spot in the library parking lot follows a normal distribution with a mean of 5.5 minutes and a standard deviation of 1 minute. Find the probability that a randomly selected college student will take between 4.0 and 6.5 minutes to find a parking spot in the library lot. 29) _____ A) 0.2255 B) 0.7745 C) 0.0919 D) 0.4938 Use a normal probability plot to asses whether the sample data could have come from a population that is normally distributed. 30) Determine whether the following normal probability plot indicates that the sample data could have come from a population that is normally distributed. 30) _____ A) not normally distributed B) normally distributed Provide an appropriate response. 31) The tread life of a particular brand of tire is a random variable best described by a normal distribution with a mean of 60,000 miles and a standard deviation of 2700 miles. What warranty should the company use if they want 96% of the tires to outlast the warranty? 31) _____ A) 57,300 mi B) 62,700 mi C) 64,725 mi D) 55,275 mi 32) Find the z-score that is greater than the mean and for which 70% of the distribution's area lies to its left. _____ 32) A) 0.53 B) 0.98 C) 0.47 D) 0.81 33) Compare a graph of the normal density function with mean of 0 and standard deviation of 1 with a graph of a normal density function with mean equal to 4 and standard deviation of 1. The graphs would 33) _____ A) Have no horizontal displacement but one would be flatter than the other. B) Have no horizontal displacement but one would be steeper that the other. C) Have the same height but one would be shifted 4 units to the right. D) Have the same height but one would be shifter 4 units to the left. 34) A national caterer determined that 87% of the people who sampled their food said that it was delicious. A random sample of 144 people is obtained from a population of 5000. The 144 people are asked to sample the caterer's food. If the sample proportion saying that the food is delicious, what is the mean of the sampling distribution of _____ ? is 34) A) 1.25 B) 0.87 C) 0.42 D) 0.19 35) A farmer was interest in determining how many grasshoppers were in his field. He knows that the distribution of grasshoppers may not be normally distributed in his field due to growing conditions. As he drives his tractor down each row he counts how many grasshoppers he sees flying away. After several rows he figures the mean number of flights to be 57 with a standard deviation of 12. What is the probability of the farmer will count 52 or fewer flights on average in the next 40 rows down which he drives his tractor? 35) _____ A) 0.0041 B) 0.0410 C) 0.4959 D) 0.9959 36) The average score of all golfers for a particular course has a mean of 73 and a standard deviation of 3. Suppose 36 golfers played the course today. Find the probability that the average score of the 36 golfers exceeded 74. 36) _____ A) 0.1293 B) 0.0228 C) 0.4772 D) 0.3707 37) Smith is a weld inspector at a shipyard. He knows from keeping track of good and substandard welds that for the afternoon shift 5% of all welds done will be substandard. If Smith checks 300 of the 7500 welds completed that shift, would it be unusual for Smith to find 30 or more substandard welds? 37) _____ A) No B) Yes 38) The owner of a computer repair shop has determined that their daily revenue has mean $7200 and standard deviation $1200. The daily revenue totals for the next 30 days will be monitored. What is the probability that the mean daily revenue for the next 30 days will exceed $7500? 38) _____ A) 0.9131 B) 0.0853 C) 0.0869 D) 0.9147 39) Parking at a large university has become a very big problem. University administrators are interested in determining the average parking time (e.g. the time it takes a student to find a parking spot) of its students. An administrator inconspicuously followed 110 students and carefully recorded their parking times. Identify the population of interest to the university administration. 39) _____ A) the students that park at the university between 9 and 10 AM on Wednesdays B) the entire set of faculty, staff, and students that park at the university C) the parking times of the entire set of students that park at the university D) the parking times of the 110 students from whom the data were collected Determine whether the study depicts an observational study or an experiment. 40) The personnel director at a large company would like to determine whether the company cafeteria is widely used by employees. She calls each employee and asks them whether they usually bring their own lunch, eat at the company cafeteria, or go out for lunch. 40) _____ A) observational study B) experiment Construct a frequency distribution for the data using five classes. Describe the shape of the distribution. 41) The data set: weekly grocery bills (in dollars) for 20 randomly selected households 41) _____ A) bell shaped B) skewed to the left C) skewed to the right D) uniform The following double-bar graph illustrates the revenue for a company for the four quarters of the year for two different years. Use the graph to answer the question. 42) In what quarter was the revenue the greatest for 2000? A) first quarter B) fourth quarter C) third quarter D) second quarter 42) _____ Provide an appropriate response. 43) For the distribution drawn here, identify the mean, median, and mode. A) A = mean, B = mode, C = median C) A = mode, B = mean, C = median 43) _____ B) A = mode, B = median, C = mean D) A = median, B = mode, C = mean 44) A history instructor has given the same pretest and the same final examination each semester. He is interested in determining if there is a relationship between the scores of the two tests. He computes the linear correlation coefficient and notes that it is 1.15. What does this correlation coefficient value tell the instructor? 44) _____ A) There is a strong positive correlation between the tests. B) There is a strong negative correlation between the tests. C) The history instructor has made a computational error. D) The correlation is something other than linear. Provide an appropriate response. Express your answer as a simplified fraction unless otherwise noted. 45) If two events A and B are __________, then P(A and B) = P(A) P(B). 45) _____ A) simple events B) independent C) complements D) mutually exclusive Provide an appropriate response. 46) Which of the below is not a requirement for binomial experiment? A) The trials are mutually exclusive. B) The probability of success is fixed for each trial of the experiment. C) For each trial there are two mutually exclusive outcomes. D) The experiment is performed a fixed number of times. 46) _____ 47) The probability that a house in an urban area will develop a leak is 5%. If 20 houses are randomly selected, what is the mean of the number of houses that developed leaks? 47) _____ A) 1.5 B) 2 C) 1 D) 0.5 48) A recent article in the paper claims that government ethics are at an all-time low. Reporting on a recent sample, the paper claims that 40% of all constituents believe their representative possesses low ethical standards. Suppose 20 of a representative's constituents are randomly and independently sampled. Assuming the paper's claim is correct, find the probability that more than eight but fewer than 12 of the 20 constituents sampled believe their representative possesses low ethical standards. 48) _____ A) 0.562821 B) 0.230733 C) 0.534680 D) 0.347875 49) The graph of a normal curve is given. Use the graph to identify the value of μ and σ. 49) _____ A) μ = 32, σ = 849 B) μ = 849, σ = 32 C) μ = 96, σ = 849 D) μ = 849, σ = 96 50) Find the area under the standard normal curve between z = 1.5 and z = 2.5. A) 0.9332 B) 0.0606 C) 0.9938 D) 0.9816 50) _____ 51) John has six bills of paper money in the following denominations: $1, $5, $10, $20, $50, and $100 If he selects 3 bills at a time how many, how many groups can be formed? 51) _____ A) 15 B) 30 C) 10 D) 20 52) The number of violent crimes committed in a day possesses a distribution with a mean of 4.9 crimes per day and a standard deviation of 3 crimes per day. A random sample of 100 days was observed, and the mean number of crimes for the sample was calculated. Describe the sampling distribution of the sample mean. 52) _____ A) approximately normal with mean = 4.9 and standard deviation = 0.3 B) shape unknown with mean = 4.9 and standard deviation = 0.3 C) approximately normal with mean = 4.9 and standard deviation = 3 D) shape unknown with mean = 4.9 and standard deviation = 3 Determine whether the study depicts an observational study or an experiment. 53) A pollster obtains a sample of students and asks them how they will vote on an upcoming referendum. 53) _____ A) experiment B) observational study Provide an appropriate response. 54) Many firms use on-the-job training to teach their employees new software. Suppose you work in the personnel department of a firm that just finished training a group of its employees in new software, and you have been requested to review the performance of one of the trainees on the final test that was given to all trainees. The mean and standard deviation of the test scores are 80 and 2, respectively, and the distribution of scores is bell shaped. What percentage of test-takers scored better than a trainee who scored 74? 54) _____ A) approximately 95% B) approximately 97.5% C) approximately 99.85% D) approximately 84% 55) A recent survey found that 70% of all adults over 50 wear sunglasses for driving. In a random sample of 10 adults over 50, what is the probability that at least six wear sunglasses? 55) _____ A) 0.850 B) 0.700 C) 0.006 D) 0.200 56) Furnace repair bills are normally distributed with a mean of 270 dollars and a standard deviation of 20 dollars. If 64 of these repair bills are randomly selected, find the probability that they have a mean cost between 270 dollars and 272 dollars. 56) _____ A) 0.7881 B) 0.2119 C) 0.2881 D) 0.5517 The pie chart shows the percentage of votes received by each candidate in the student council presidential election. Use the pie chart to answer the question. 57) Who got the most votes? 57) _____ A) Ben B) Jim C) Ming D) Ann Provide an appropriate response. 58) We believe that 90% of the population of all Calculus I students consider calculus an exciting subject. Suppose we randomly and independently selected 21 students from the population. If the true percentage is really 90%, find the probability of observing 20 or more of the students who consider calculus to be an exciting subject in our sample of 21. 58) _____ A) 0.364730 B) 0.255311 C) 0.109419 D) 0.635270 59) Given a distribution that follows a standard normal curve, what does the graph of the curve do as z increases in the positive direction? 59) _____ A) The graph of the curve eventually intersects the horizontal axis. B) The graph of the curve approaches zero. C) The graph of the curve approaches an inflection point. D) The graph of the curve approaches 1. 60) A greenhouse in a tri-county area has kept track of its customers for the last several years and has determined that 28% of its customers plant a vegetable garden in the spring. The greenhouse obtains a random sample of 1000 of its customers. What is the mean of the sampling distribution of garden in the spring? 60) _____ A) 2800 B) 0.72 C) 0.28 D) 0.002 , the sample proportion of customers that plant a vegetable 1) A 2) C 3) C 4) E 5) A 6) B 7) C 8) D 9) A 10) B 11) A 12) D 13) B 14) A 15) D 16) D 17) B 18) B 19) B 20) B 21) A 22) A 23) D 24) C 25) A 26) A 27) C 28) B 29) B 30) A 31) D 32) A 33) C 34) B 35) A 36) B 37) B 38) B 39) C 40) A 41) A 42) B 43) B 44) C 45) B 46) A 47) C 48) D 49) B 50) B 51) D 52) A 53) B 54) C 55) A 56) C 57) A 58) A 59) B 60) C