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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         B) single-blind design
C) matched-pairs 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         and               anorexia levels were reported. How many levels does the treatment
have in this experiment?           3) _____

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           (minimum
250 at-bats). Based on this information, which measure of variation could be calculated? 9) _____

A) range        B) variance
C) percentile   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,               Using the method of least squares, the faculty group obtained

the following prediction equation,                       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   = -2.75x + 96.14. Determine the residual of a data point for which x = 4 and
y = 82.


                                                                                            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   = 1.488x + 60.46. Determine the residual of a data point for which x = 53
and y = 145.


                                                                                   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.    19) _____
A) Prediction set      B) Sample space
C) Bernoulli space     D) Event set

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            Probability
Red              0.2299
Green            0.1908
Orange           0.2168
Yellow           0.1889
Purple           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                 and a standard deviation of 0.04 ounce.
Find the probability that the bottle contains fewer than               of beer.     28) _____

A) 0.4938        B) 0.0062        C) 0.5062       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      is

the sample proportion saying that the food is delicious, what is the mean of the sampling distribution of       ?    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?        42) _____
A) first quarter B) fourth quarter
C) third quarter D) second quarter

Provide an appropriate response.
43)




For the distribution drawn here, identify the mean, median, and mode.     43) _____

A) A = mean, B = mode, C = median         B) A = mode, B = median, C = mean
C) A = mode, B = mean, C = median         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?         46) _____
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.

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.       50) _____
A) 0.9332        B) 0.0606       C) 0.9938      D) 0.9816

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    , the sample proportion of customers that plant a vegetable
garden in the spring? 60) _____

A) 2800 B) 0.72 C) 0.28 D) 0.002
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

				
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