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Chapter 16 l Skills Practice 975
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Skills Practice Skills Practice for Lesson 16.1
Name _____________________________________________ Date ____________________
Choosing CirclesSampling Methods and Bias
VocabularyMatch each definition to its corresponding term.
1. a sample obtained by dividing the population a. subjective sample
into different groups, or strata, according to a
characteristic and randomly selecting data
from each group
2. a sample selected in such a way that every b. simple random sample
member of the population has the same
chance of being selected
3. a sample whose data is based on what is c. random digit table
convenient for the person choosing the sample
4. a sample obtained by selecting every nth data d. stratified random sample
in the population
5. a table of single digits, 0 through 9, that have e. cluster sample
been randomly generated by a computer so
that every digit has the same chance of
being chosen each time
6. a sample whose data consists of those f. systematic sample
who volunteer to be part of the sample
7. a sample of data that does not accurately g. convenience sample
represent all of the population
8. a sample obtained by creating clusters with h. volunteer sample
each cluster containing the characteristics of
the population and randomly selecting a cluster
9. a sample in which an individual makes a judgment i. biased sample
about which data items to select
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16Problem SetSelect a subjective sample of four for each data set. Explain the criteria on which you selected your sample.
1. The test scores for a math test are shown.
70 75 89 60 95 78 54 82 91 76
Answers will vary. Sample answer: 54, 75, 76, 95
54 and 95 were chosen because they are the maximum and minimum values.
75 and 76 were chosen because they are about in the middle of the highest and lowest test scores.
2. The weights in kilograms of wildebeest in a zoo are shown.
130 242 227 186 250 192 215 203 232 175
3. The number of crimes committed each month over a ten-month period are shown.
2 1 0 3 3 4 5 2 0 6
4. The prices of DVDs in an electronics store, in dollars, are shown.
5.99 7.95 10.00 14.75 8.35 13.95 21.99 13.27 8.75 11.95
5. The batting averages of ten baseball players in a season are shown.
0.120 0.215 0.240 0.283 0.175 0.160 0.220 0.302 0.254 0.193
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6. The heights of ten buildings in a city, in feet, are shown.
102 54 76 95 250 37 65 48 27 85
For each data set, use your calculator or the random digit table below to generate four random numbers between 1 and 10. Then use the numbers you generated to create a random sample of four from the data set.
Random Digit Table
Line 1 65285 97198 12138 53010 94601 15838 16805 61004 43516 17020
Line 2 17264 57327 38224 29301 31381 38109 34976 65692 98566 29550
Line 3 95639 99754 31199 92558 68368 04985 51092 37780 40261 14479
Line 4 61555 76404 86210 11808 12841 45147 97438 60022 12645 62000
Line 5 78137 98768 04689 87130 79225 08153 84967 64539 79493 74917
Line 6 62490 99215 84987 28759 19177 14733 24550 28067 68894 38490
Line 7 24216 63444 21283 07044 92729 37264 13211 37485 10415 36457
Line 8 16975 95428 33226 55903 31605 47517 22250 03918 46999 98501
Line 9 59138 39542 71168 57609 91510 77904 74244 50940 31553 62562
Line 10 29478 59652 50414 11966 87912 87154 12944 49862 96566 48825
Line 11 96155 95009 27429 72918 08457 78134 48407 26061 58754 05326
Line 12 29621 66583 62966 12468 20245 14015 04014 35713 03980 03024
Line 13 12639 75291 71020 17265 41515 64074 64629 63293 53307 48766
Line 14 14544 37134 54714 02401 63228 26831 19386 15457 17999 18306
Line 15 83403 88827 09834 11333 68431 31706 26652 04711 34593 22561
Line 16 67642 05204 30697 44806 16989 68405 85621 45556 35434 09532
Line 17 64041 99011 14610 40273 09482 65864 01573 82274 81446 32477
Line 18 17048 94523 97444 59994 16515 39364 97551 65629 63932 03091
Line 19 93039 89416 52795 10631 09728 68202 20963 02477 55494 39563
Line 20 82244 34392 96607 17226 51984 10753 76272 50985 97593 34320
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7. Each doctor in a town is given a phone number that ends in the digits 0001 through 0010.
Phone
Number0001 0002 0003 0004 0005 0006 0007 0008 0009 0010
Doctor’s
NameThomas Easton Wu Rodriguez Pasles Farris Shea Wong Price Siegelman
Answers will vary. Sample answer: 0002, 0003, 0008, 0010 Easton, Wu, Wong, Siegelman
8. Each contestant participating in a contest is assigned a number.
Contestant Number 1 2 3 4 5 6 7 8 9 10
Contestant’s Name Lia Joe Ariel Jess Victor Roberto Wen Anita Mia Ana
9. Ten students record the number of times a coin is flipped until it lands on heads.
Trial Number 1 2 3 4 5 6 7 8 9 10
Number of Flips 1 1 1 2 3 4 1 5 2 1
10. A factory worker records the weights, in ounces, of the first ten bolts that he manufactured.
Bolt Number 1 2 3 4 5 6 7 8 9 10
Weight 2.1 2.2 2.3 2.4 2.2 2.1 2.3 2.1 2.2 2.1
11. The prices of cars at ten different dealerships are shown.
Dealership 1 2 3 4 5
Price 24,500 32,000 27,750 23,450 26,875
Dealership 6 7 8 9 10
Price 66,000 22,750 23,650 24,735 37,500
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12. A coach records the heights of players on her softball team, in meters.
Player 1 2 3 4 5 6 7 8 9 10
Height 1.8 1.5 1.6 1.6 2.2 1.3 1.7 1.8 2.0 2.1
In Exercises 13 through 18, use the given data set to create a stratified random sample of the specified size. Explain the criteria by which you selected your sample.
13. The data set below shows the highest temperature recorded for select cities on
different continents.
Highest Temperature Recorded
North America Europe Asia Africa
81 95 94 101
92 81 86 96
90 102 92 103
104 98 97 94
87 87 107 98
111 103 91 107
76 92 102 97
94 97 97 98
95 100 93 112
89 96 88 96
a. Create a stratified random sample of 4 temperatures.
Sample answer: {81, 103, 97, 98}; I randomly chose one temperature from each of the four continents.
b. Create a stratified random sample of 8 temperatures.
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14. The data set below shows the number of books read by the students in four different
English classes.
Number of Books Read in Each Teacher’s Class
Mr. James Ms. Farley Mr. Nguyen Ms. Razali
2 0 3 8
4 6 12 0
3 2 8 4
11 13 8 0
2 8 4 15
7 6 4 8
2 3 9 0
11 12 4 14
0 3 1 6
8 2 0 6
a. Create a stratified random sample with 12 data values to describe the number of
books read by the students.
b. Create a stratified random sample with 16 data values to describe the number of
books read by the students.
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15. The data set below shows the number of cars crossing an intersection every hour for
8 hours during 4 days.
Number of Cars Crossing an Intersection
Day 1 Day 2 Day 3 Day 4
124 234 184 192
213 249 253 268
276 281 279 264
302 321 314 319
354 342 349 368
312 324 313 305
297 284 287 279
251 264 255 256
a. Create a stratified random sample with 16 data values to describe the number of
cars crossing the intersection hourly.
b. Create a stratified random sample with 24 data values to describe the number of
cars crossing the intersection.
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16. A group of five doctors takes turns volunteering in a hospital. Each doctor volunteers
for a period of eight days, and then it is the next doctor’s turn. The data set below
shows the number of patients that each doctor saw during their volunteer period.
Number of Patients Seen
Dr. Kim Dr. Rodriguez Dr. Lao Dr. Woods Dr. Morena
16 18 13 19 17
15 16 17 18 16
21 23 24 19 21
26 27 24 29 28
24 23 19 26 23
27 28 26 24 27
13 15 17 16 14
18 16 14 17 18
a. Create a stratified random sample with 5 data values to describe the number of
patients seen daily.
b. Create a stratified random sample with 15 data values to describe the number of
patients seen.
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17. The data set below shows the amounts of recycled material collected, in pounds, from
six different neighborhoods each month for four months.
Recycled Material Collected from Six Neighborhoods (in pounds)
Arlington Sylvia Burns Beaverton Bayview Hillsdale
426 482 431 324 274 134
435 324 521 675 184 162
425 398 425 573 234 176
441 436 486 543 246 186
a. Create a stratified random sample with 12 data values to describe the amount of
recycled material collected monthly.
b. Create a stratified random sample with 18 data values to describe the amount of
recycled material collected.
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18. The data set below shows the number of people who visit a soup kitchen on certain days.
Number of People Who Visit a Soup Kitchen
Monday Wednesday Friday Sunday
42 56 86 112
43 57 87 124
49 52 92 126
48 61 93 118
38 57 96 116
46 53 87 117
41 48 86 128
48 52 87 127
a. Create a stratified random sample with 16 data values to describe the number of
daily visitors to the soup kitchen.
b. Create a stratified random sample with 20 data values to describe the number of
daily visitors to the soup kitchen.
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Create two different clustered samples for each data set. Explain the criteria by which you selected each sample.
19. Weights of Polar Bears at Three Zoos (in pounds)
Bronx Zoo San Diego Zoo Philadelphia Zoo
875 892 884
1295 1216 1237
1416 1375 1384
The weights from any one (or two) of the zoos are acceptable as a clustered sample.
Example: {892, 1216, 1375}. I chose the weights of all the polar bears in the San Diego Zoo.
Example: {884, 1237, 1384}. I chose the weights of all the polar bears in the Philadelphia Zoo.
20. Attendance at a Movie Theatre on Three Weekdays
Monday Tuesday Wednesday
134 94 112
142 134 141
197 213 206
223 227 216
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21. Length of Time of Games for Four Baseball Teams (in minutes)
Pirates A’s Rays Bulldogs
116 123 124 108
124 126 122 123
137 136 142 129
128 126 127 128
153 148 153 149
22. Students’ Scores on Math Tests
Hugo Miriam Anastasia Nick
85 79 82 83
78 76 72 79
69 72 71 67
82 86 78 84
73 75 72 71
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23. Number of Daily Customers for a Bank
Week 1 Week 2 Week 3 Week 4 Week 5
123 145 94 113 127
93 88 96 102 94
94 104 93 97 89
154 174 163 164 173
213 197 204 192 216
24. Daily Prices of a Stock on Each Weekday over 5 Weeks
Week 1 Week 2 Week 3 Week 4 Week 5
2.89 2.77 3.21 2.42 0.69
3.81 4.09 4.66 1.77 1.35
1.48 1.82 1.07 0.96 1.10
3.86 0.98 4.56 3.52 3.33
2.27 3.70 2.59 0.91 1.71
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Determine the type of sampling technique being used in each situation. Choose from simple random sampling, cluster sampling, stratified sampling, systematic sampling, subjective sampling, convenience sampling, or volunteer sampling.
25. A teacher chooses the first student in each row to do a math problem at the board.
systematic sampling
26. A physical education teacher chooses the five students with the best times in a
cross country event.
27. A principal randomly chooses eight student ID numbers to participate in a survey.
28. A teacher chooses students with their hands in the air to put problems on the board.
29. A principal chooses the first 12 students into the auditorium to help pass out programs.
30. A teacher chooses her favorite 8 problems from the lesson to demonstrate to the class.
Determine whether each study has a source of bias. If so, describe the bias and explain why the bias makes the sample unrepresentative.
31. A survey is mailed to voters in Albany asking “Will you vote for the sales tax
increase in Albany?”
There is no bias in this study.
32. A survey is mailed to voters in Albany who make more than $100,000 a year asking,
“Will you vote for the sales tax increase in Albany?”
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33. A medical company uses healthy patients to test their drugs for side effects.
34. A medical company uses sick patients to test their competitors’ drugs for
side effects.
35. A poll by the Department of Education is conducted online that asks, “Do you have
a computer at home?”
36. A survey that measures the popularity of a magazine is inserted into the magazine
asking, “Do you like this magazine?”
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Skills Practice Skills Practice for Lesson 16.2
Name _____________________________________________ Date ____________________
Surveys and Studies and Experiments, Oh My!Surveys, Studies, and Experiments
VocabularyProvide an example of each term.
1. sample survey
2. observational study
3. experiment
4. treatment
5. experimental unit
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6. confounding
Problem SetClassify each situation as a sample survey, an observational study, or an experiment. Explain your reasoning.
1. A teacher wanted to know if students who study for more than two hours for a test
will get a better grade on the test than students who study for two hours or less.
She asks her students to log their study time for the test. She gathers data from
three classes taking the test.
This is an observational study since the teacher did not try to influence the data.
2. One hundred middle school math students are randomly divided into two groups,
one in which a 4-function calculator is used at all times and one in which a
4-function calculator is never used. The principal wants to determine if student
grades are higher if they can always use a calculator.
3. To determine if there is a link between environmental factors and cancer in women,
researchers examined the rate of cancer for 10,000 women who are sisters of
previous cancer patients. The researcher asked the women to respond to 50
questions about their environment as they were growing up.
4. A medical researcher who wants to test the efficacy of a drug on humans divides
1000 volunteers into two groups, one which will receive the drug, and one which
will receive a placebo (a treatment not including the drug being tested).
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5. To determine if there is a link between the number of hours a student oversleeps
and student grades, a teacher asked 125 students to track the number of minutes
they oversleep each day for a month.
6. A medical researcher who wants to see if there is a link between the weight of a
patient and the patient’s blood pressure asks 100 doctors to track the weight and
blood pressure of one-half of their patients who are randomly chosen and answer
specific questions about each patient.
For each situation, identify the population, the sample, and the characteristic of interest.
7. A teacher wanted to know if students who study for more than two hours for a test
will get a better grade on the test than students who study for two hours or less.
She asks her students to log their study time for the test. She gathers data from
three classes taking the test.
The population is students. The sample is the students in three classes. The characteristic is the link between study time and performance on the test.
8. One hundred middle school math students are randomly divided into two groups,
one in which a 4-function calculator is used at all times and one in which a
4-function calculator is never used. The principal wants to determine if student
grades are higher if they can always use a calculator.
9. To determine if there is a link between environmental factors and cancer in women,
researchers examined the rate of cancer for 10,000 women who are sisters of
previous cancer patients. The researcher asked the women to respond to 50
questions about their environment as they were growing up.
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10. A medical researcher who wants to test the efficacy of a drug on humans divides
1000 volunteers into two groups, one which will receive the drug, and one which
will receive a placebo (a treatment not including the drug being tested).
11. To determine if there is a link between the number of hours a student oversleeps
and student grades, a teacher asked 125 students to track the number of minutes
they oversleep each day for a month.
12. A medical researcher who wants to see if there is a link between the weight of a
patient and the patient’s blood pressure asks 100 doctors to track the weight and
blood pressure of one-half of their patients who are randomly chosen and answer
specific questions about each patient.
Determine an unbiased question for each survey that is worded so that it can be answered accurately.
13. A news station wants to conduct a survey to determine what percent of city
residents support a new law to ban texting while driving.
Answers will vary. Sample answer: If you use a cell phone while driving, would you support a new law to ban texting while driving?
14. A science teacher wants to conduct a survey to determine how often students wear
safety goggles while using a Bunsen burner.
15. A medical research group wants to conduct a survey to determine how many
women over 50 have high blood pressure.
16. A principal of a high school wants to conduct a survey to determine what percent
of students participate in two or more school sports per year.
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17. A band student parent group wants to conduct a survey to determine what percent
of parents are willing to sponsor the purchase of new instruments.
18. A school board wants to conduct a survey of city residents to see if they would
support a decrease in funding for sophomore sports.
Explain how confounding could have occurred for each observational study.
19. A teacher wanted to know if students who use graphing calculators use programs
to help them evaluate formulas. She asks her students whether they use graphing
calculator programs to evaluate formulas. She gathers data from three classes.
The concern is if students write their own programs as opposed to using professionally developed ones to evaluate formulas. If students write their own, they may not know the correct steps for evaluating formulas.
20. To determine if there is a link between eating breakfast and student grades, a
teacher asked 125 students to track the number of days each week for a month
that they eat breakfast before coming to school.
21. A parent-teacher group wants to see if there is a link between the occupation of a
parent and the level of participation in volunteer activities that the group sponsors. They
send a letter to parents of 300 random students in the school and ask them to list their
occupation and level of participation in volunteer activities sponsored by their group.
22. A study conducted by the owner of an art school wants to know if the total
enrollment in his weekday classes will increase if he drops the canvas fee.
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23. A study used by a news agency wants to know if there is link between the income
level in a family and whether they have a parent in a nursing home.
24. A politician wants to see if there is a link between the income level of his
constituents and the amount of money they are willing to contribute to his campaign.
Identify the treatments in each experiment. Then determine how the differences in treatments can be analyzed and interpreted in order to draw a conclusion.
25. One hundred geometry students are randomly divided into 4 classes – one in which
a drawing program is used at all times to draw geometric shapes and one in which
a drawing program is never used. The department chair wants to determine if
students’ geometry grades are higher if they have to draw a geometric figure with a
drawing program.
There are two treatments. One uses a drawing program and the other does not. The differences in treatments were analyzed by recording the grades for specific tests that included analyzing geometric figures and then comparing the grades on the tests.
26. Sixty juniors are randomly chosen and divided into two groups – one in which
all students participate in an extra-curricular activity and the other in which no
students participate in an extra-curricular activity. The Student Council sponsor
wants to determine if student grades are higher at the end of the year if students
participated in an extra-curricular activity during the school year.
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27. Five hundred people are randomly chosen from the community and divided into
two groups – one which will focus on the effects of being on a prescribed high-protein,
low fat diet for six months and the other on the effects of not being on that diet.
The manufacturer of the diet wants to see if the diet results in a significant weight
loss for its participants.
28. To determine if there is a link between the use of an acne medicine and weight
loss, the manufacturer of the medicine asks 100 doctors who prescribe the
medicine to record the weight before prescribing the medicine and then after their
patients have been on the medicine for six months. The manufacturer also asks
the same doctors to record the weight of 100 patients who are not on the medicine
both at the beginning and at the end of the six-month period.
29. A medical researcher who wants to determine how a drug is processed in the liver
divides 100 mice into two groups – one that will receive the drug, and one that will
receive a placebo (a treatment not including the drug being tested).
30. Three hundred 30-year olds are randomly chosen and divided into three groups – one
in which all participants received a four-year college degree, a second in which all
participants received a two-year college degree, and the third in which no participant
had a college education. The focus group for a college wants to determine how the
income level of each group is related to the number of years of college.
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Skills Practice Skills Practice for Lesson 16.3
Name _____________________________________________ Date ____________________
Do It YourselfDesigning and Collecting Data Using a Survey, Study, or Experiment
Problem SetEach of the following questions is best answered by a survey, a study, or an experiment. Identify the best method to use. Then explain how you would obtain a random sample and why the technique you chose is appropriate.
1. You want to determine the average income of public school teachers in a certain city.
Answers will vary. Sample answer: a study. Assign each public school teacher an ID number and use a computer to randomly generate a sample of teachers. This technique provides a random sample of the population of teachers in the city, and random sampling is typically representative of a population.
2. You want to compare the average income of male and female public school
teachers in a certain city.
3. A company wants to determine whether their drugs are harmful to people in the
following age groups: 0–10, 11–21, 22–35, and 40 and above.
4. A company wants to determine whether their drugs are harmful to people in a
certain vicinity.
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5. A university wants to study the economy of towns that have a heavy drug
presence, but they can only study three towns.
6. A local hospital wants to compare the effects of drugs on people in the age groups
14 –17 and 18 –23.
For each survey, observational study, or experiment, determine which of the following sampling techniques would be the most appropriate: random sampling, stratified random sampling, or clustered sampling. Then explain how you would obtain a sample and why the technique you chose is appropriate.
7. A newspaper wants to determine which areas of town have the least number of
subscriptions.
Sample answer: stratified random sampling; Divide the population of the town into groups according to their geographic location (possibly north, south, east, west), and randomly select members from each group. This technique provides a random sample from all areas of town. Random sampling is typically representative of a population.
8. You want to estimate the number of people in your school who are vegetarians.
9. You want to determine whether 9th graders or 11th graders are more likely to be
vegetarians.
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10. A political campaign can only visit three neighborhoods. They want to see how well
liked their candidate is.
11. Health and Human Services wants to count the number of homeless people in a
town. They only have enough counters to cover one-fifth of the town.
12. A manufacturer wants to test the taste of their frozen vegetables as the bags of
vegetables come out of a freezer.
Determine the population of interest in each situation.
13. You want to determine the average income of public school teachers in a certain city.
The population of interest is all public school teachers in the city.
14. You want to compare the average income of male and female public school
teachers in a certain city.
15. A company wants to determine whether their drugs are harmful to people in the
following age groups: 0–10, 11–21, 22–35, and 40 and above.
16. A company wants to determine whether their drugs are harmful to people in a
certain vicinity.
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17. A university wants to study the economy of towns that have a heavy drug
presence, but they can only study three towns.
18. A local hospital wants to compare the effects of drugs on people in the age groups 14–17
and 18–23.
Determine the characteristic of interest in each situation.
19. You want to determine the average income of public school teachers in a certain city.
The characteristic of interest is the average income of public school teachers in a certain city.
20. You want to compare the average income of male and female public school
teachers in a certain city.
21. A company wants to determine whether their drugs are harmful to people in the
following age groups: 0–10, 11–21, 22–35, and 40 and above.
22. A company wants to determine whether their drugs are harmful to people in a
certain vicinity.
23. A university wants to study the economy of towns that have a heavy drug
presence, but they can only study three towns.
24. A local hospital wants to compare the effects of drugs on people in the age groups
14–17 and 18–23. Determine the characteristic of interest as if the researcher did
not specify the length of time the doctor had treated the patient.
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Identify and explain any possible sources of bias in the given situation.
25. A cell phone company wants to know how many times adults typically use
text-messaging in one month. The company asks a random sample of adults
that subscribe to their cell phone service, “How many times did you text-message
last month?”
Answers will vary. Sample answer: The sample is biased because they only asked adults that use their cell phone service, and this may not be representative of the adult population using cell phones. It is also biased because “last month” may have been a month with an atypical volume of cell-phone usage.
26. A principal wants to know if students should be allowed to use cell phones while
in the classroom. She surveys one math class to see how many students have cell
phones and asks them how they could use their cell phones to improve instruction.
27. A principal wants to know if students should be allowed to use graphing calculators
in the classroom. She surveys one English class and asks, “How do you use a
graphing calculator to improve instruction?”
28. A teacher wants to know how students use graphing calculators while in the
classroom. She asks volunteers for suggestions.
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29. A principal wants to know which topics students need to discuss with her. She
sends out a survey to 1000 students. Only 25 respond.
30. The teacher wants to know how many hours are spent reading each week. She asks
the first 10 students who pass her room, “How many hours do you spend reading
each week?”
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Skills Practice Skills Practice for Lesson 16.4
Name _____________________________________________ Date ____________________
Numbers, Graphs, and ConclusionsInterpreting Results and Drawing Conclusions from a Survey, Study, or Experiment
Problem SetCreate a dot plot for each set of data.
1. The following data represent the number of home runs hit by baseball players.
17, 12, 16, 21, 19, 15, 16, 22, 12, 21, 19, 18, 12, 15, 17
11 12 13 14 15 16 17
Number of Home Runs Hit18 19 20 21 22 23
2. The following data represent the salaries in thousands of dollars of employees in a company.
38, 40, 32, 41, 40, 31, 30, 41, 39, 39, 30, 42, 31, 31, 32
3. The following data represent the heights in inches of people in an aerobics class.
70, 69, 65, 60, 62, 64, 73, 65, 66, 60, 66, 65
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4. The following data represent the number of hours that employees at a restaurant
worked last week.
22, 35, 40, 42, 24, 36, 40, 30, 40, 38, 22, 36, 40, 40, 42, 40, 35, 24
5. The following data represent the lengths in inches of fish in an aquarium.
20, 22, 20, 19, 14, 12, 18, 20, 14, 21, 20, 15, 19, 14, 19, 19, 21, 12, 20, 21, 22
6. The following data represent students’ English test scores.
77, 94, 89, 86, 90, 68, 95, 91, 90, 89, 77, 79, 82, 68, 90, 91, 86, 87, 89, 90, 90
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Create a histogram for each set of data.
7. The following data represent the number of home runs hit by baseball players.
17, 12, 16, 21, 19, 15, 16, 22, 12, 21, 19, 18, 12, 15, 17
11–15
2
4
6
8
16–20 21–25
Number of Home Runs Hit
Nu
mb
er o
f P
eop
le
8. The following data represent the salaries in thousands of dollars of employees in a
company. 38, 40, 32, 41, 40, 31, 30, 41, 39, 39, 30, 42, 31, 31, 32
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9. The following data represent the heights in inches of people in an aerobics class.
70, 69, 65, 60, 62, 64, 73, 65, 66, 60, 66, 65
10. The following data represent the number of hours that employees at a restaurant
worked last week. 22, 35, 40, 42, 24, 36, 40, 30, 40, 38, 22, 36, 40, 40, 42, 40, 35, 24
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11. The following data represent the lengths in inches of fish in an aquarium. 20, 22,
20, 19, 14, 12, 18, 20, 14, 21, 20, 15, 19, 14, 19, 19, 21, 12, 20, 21, 22
12. The following data represent students’ English test scores. 77, 94, 89, 86, 90, 68,
95, 91, 90, 89, 77, 79, 82, 68, 90, 91, 86, 87, 89, 90, 90
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Create a stem-and-leaf plot for each set of data.
13. The following data represent the number 14. The following data represent the salaries
of home runs hit by baseball players. in thousands of dollars of employees
17, 12, 16, 21, 19, 15, 16, 22, 12, 21, in a company. 38, 40, 32, 41, 40, 31,
19, 18, 12, 15, 17 30, 41, 39, 39, 30, 42, 31, 31, 32
Number of Home Runs Hit
1 2 2 2 5 5 6 6 7 7 8 9 9
2 1 1 2
2⏐1 = 21 Runs
15. The following data represent the heights 16. The following data represent the number
in inches of people in an aerobics class. of hours that employees at a restaurant
70, 69, 65, 60, 62, 64, 73, 65, 66, 60, worked last week. 22, 35, 40, 42, 24, 36, 40,
66, 65 30, 40, 38, 22, 36, 40, 40, 42, 40, 35, 24
17. The following data represent the lengths 18. The following data represent students’
in inches of fish in an aquarium. 20, 22, 20, English test scores. 77, 94, 89, 86, 90, 68,
19, 14, 12, 18, 20, 14, 21, 20, 15, 19, 14, 95, 91, 90, 89, 77, 79, 82, 68, 90, 91,
19, 19, 21, 12, 20, 21, 22 86, 87, 89, 90, 90
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Create a box-and-whisker plot for each set of data.
19. The following data represent the weights in pounds of 12 players on a football team.
220, 244, 185, 261, 243, 225, 273, 282, 176, 190, 208, 214
minimum: 176, first quartile: 199, median: 222.5, third quartile: 252.5, maximum: 282
20. The following data shows the amounts of annual snowfall in inches for 10 northeastern
U.S. cities.
43, 32, 56, 128, 85, 96, 46, 122, 100, 68
21. The following data shows the average daily low temperatures in degrees Fahrenheit for
15 U.S. cities.
60, 44, 54, 50, 59, 53, 48, 46, 55, 56, 59, 52, 49, 55, 51
22. The following data shows the heights in feet of 11 trees in a forest.
41, 30, 22, 16, 28, 32, 27, 46, 39, 35, 20
250 260 270 280 290 300170
176 199 222.5 252.5 282
180 190 200 210 220 230 240
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23. The following data represent the total number of points scored by the 11 players on
a basketball team.
12, 28, 11, 2, 17, 5, 20, 26, 7, 2, 18
24. The following data represent the ages of 13 students in an adult karate class.
26, 35, 45, 22, 23, 30, 26, 47, 33, 35, 40, 32, 51
Determine the mean, median, and mode of each data set. Tell if the data is symmetric.
25. The following data represent the amounts of time in minutes that it takes nine
different people to get to work.
15, 20, 30, 10, 55, 45, 25, 20, 30
Mean � 27.78
Median � 25
Modes � 20, 30
Symmetry: not symmetric
26. The following data represent the long jump distances in feet of 12 participants
in a track meet.
19.9, 22.1, 18.5, 20.4, 20.8, 21.3, 19.2, 20.1, 21.0, 15.2, 20.0, 21.6
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27. The following data represent the fuel efficiencies in miles per gallon of 8 cars at a
dealer. 20, 16, 32, 30, 28, 25, 24, 32
28. The following data represent the prices in dollars of 11 shirts in a store.
20, 35, 40, 20, 15, 20, 30, 25, 20, 40, 35
29. The following data represent the lengths in inches of 10 fish in an aquarium.
3, 6, 8, 11, 9, 5, 7, 6, 8, 10
30. The following data represent the number of extra-credit points earned by
14 students in a science class.
10, 15, 0, 15, 0, 5, 10, 20, 15, 0, 5, 10, 0, 0
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Determine the standard deviation and the quartiles of each data set.
31. The following data represent the amounts of time in minutes that it takes nine
different people to get to work.
15, 20, 30, 10, 55, 45, 25, 20, 30
Standard deviation: 14.39
Quartile 1: 17.5
Quartile 2: 25
Quartile 3: 37.5
32. The following data represent the long jump distances in feet of 12 participants in a
track meet.
19.9, 22.1, 18.5, 20.4, 20.8, 21.3, 19.2, 20.1, 21.0, 15.2, 20.0, 21.6
33. The following data represent the fuel efficiencies in miles per gallon of 8 cars
at a dealer.
20, 16, 32, 30, 28, 25, 24, 32
34. The following data represent the prices in dollars of 11 shirts in a store.
20, 35, 40, 20, 15, 20, 30, 25, 20, 40, 35
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35. The following data represent the lengths in inches of 10 fish in an aquarium.
3, 6, 8, 11, 9, 5, 7, 6, 8, 10
36. The following data represent the number of extra-credit points earned by
14 students in a science class.
10, 15, 0, 15, 0, 5, 10, 20, 15, 0, 5, 10, 0, 0
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