Sampling Analysis study island

A professional basketball player participated in 1,230 games in his career. He randomly chose eight games to determine the number of points he made per game, as shown below. 26, 15, 31, 15, 25, 26, 25, 26 If the sample was representative of his entire career, what was the mode of the number of points per game? A. 20 B. 25.5 C. 23.625 D. 26

D. 26

Selma wants to know if seventh grade students prefer to do their math homework in silence or with background music. She polled the 30 students in her music class. Ten students preferred to do their math homework in silence, and twenty students preferred to do their math homework with background music. Identify the sample size in the situation above. A. There is not enough information. B. 20 C. 10 D. 30

D. 30

A survey was conducted on 30 randomly selected customers on five different days to see which ice cream they order at an ice cream parlor. The table below shows the number of strawberry ice cream orders on each day. Day Strawberry Ice Cream Orders 1 5 2 7 3 6 4 9 5 8 What would be a reasonable estimate for the number of strawberry ice cream orders from a random sample of 150 orders? A. 30 B. 40 C. 25 D. 35

D. 35

The seventh grade class at a school had 269 students. The nurse called in a random sample of 10 students to measure their heights in inches, as shown below. 62, 58, 65, 66, 62, 50, 58, 50, 62, 65 If the sample was representative of the entire seventh grade, what was the mode of the heights of the seventh grade class? A. 59.8 inches B. 56 inches C. 60 inches D. 62 inches

D. 62 inches

The moderator of an online message board plans to update the board's coding and offer new features. She wants to know which feature the message board users would like her to introduce first. She created two samples by randomly selecting 40 users who have been active on the board for at least one year and 40 users who have been active less than a year. She surveyed each sample about which feature they prefer to see introduced first. The data she gathered is shown in the table below. At Least 1 Year Less Than 1 Year Direct Messaging 9 10 Updated Sort Options 9 7 Animated Emoji 4 14 Expanded User Profiles 18 9 Which statement is supported by the data in the table? A. In general, users who prefer direct messaging are more likely to have been active at least 1 year than less than 1 year. B. In general, users who have been active less than 1 year are more likely to prefer expanded user profiles to animated emoji. C. Approximately 16% of of all users prefer updated sort options be added first. D. Approximately 25% of users who have been active less than 1 year prefer direct messaging be added first.

D. Approximately 25% of users who have been active less than 1 year prefer direct messaging be added first.

Which of these is an example of a random sample? A. Henry asks five of his friends to fill out a survey to find out their favorite musicians. B. The five employees who work the late shift answer questions about management. C. The five people seated on the first row at the circus are asked their opinion about the animal acts. D. Five employees out of 2,000 are chosen randomly to complete an anonymous survey.

D. Five employees out of 2,000 are chosen randomly to complete an anonymous survey.

Jim had a collection of 28 state quarters. He poured 10 of them onto the table and noticed the years that the quarters were produced, as shown below. 2004, 2007, 2008, 2002, 2001, 2001, 2007, 2007, 2004, 2002 Assuming that the sample was representative of the collection, what was the mode of the year that the quarters were produced? A. 2007 B. 2008 C. 2004 D. 2001

A. 2007

A circus had 36 performances in one year. The entertainment company which owned the circus analyzed sales receipts for 12 of the performances and recorded the following number of t-shirt sales. 821, 696, 866, 704, 821, 775, 866, 696, 866, 704, 821, 866 Assuming that the sample was representative of all of the performances, what was the mode of the number of t-shirts sold at a performance? A. 866 B. 820.5 C. 821 D. 791.83

A. 866

The CEO of a company wanted to know how many cups of coffee his employees drank in a week. The number of cups of coffee drank by ten people are shown below. 6, 13, 3, 13, 6, 9, 6, 13, 13, 9 Assuming that the sample was representative of the entire company, what was the mean number of cups of coffee drank per week by an employee in the company? A. 9.1 B. 6.375 C. 7.65 D. 13.5

A. 9.1

A school conducted a survey to determine which sport was the students' favorite. The school asked every seventh grade student for his or her favorite sport. Were the results of the school's survey valid? A. No, because the sample was not random. B. No, because only girls were surveyed. C. Yes, because the school surveyed every seventh student that entered the school. D. Yes, because every student in the seventh grade was surveyed.

A. No, because the sample was not random.

Josh works for MooMoo Milkshakes. The company wants to know what milkshake flavor is the most popular. Today, he surveyed every third female customer on their favorite milkshake flavor. Twenty-three customers (out of 71 total) were surveyed, and 7 customers prefer MooChooChocolate, 5 customers prefer VeryStrawberry, and 11 customers prefer BananaBoBanna. Identify the sample in the situation above. A. every female customer B. today's MooMoo Milkshakes customers C. every third female customer D. every third customer

C. every third female customer

If she surveys every fifth woman that buys a ticket at the box office, this sample is ___. If she surveys every third person that enters theater four, this sample is ____. If she surveys every fourth person that walks by the concession stand, this sample is ___. If she surveys every sixth child in the arcade, this sample is___ . If she surveys every fifth person that goes through the exit, this sample is ___.

If she surveys every fifth woman that buys a ticket at the box office, this sample is not NOT RANDOM. If she surveys every third person that enters theater four, this sample is NOT RANDOM. If she surveys every fourth person that walks by the concession stand, this sample is RANDOM. If she surveys every sixth child in the arcade, this sample is NOT RANDOM. If she surveys every fifth person that goes through the exit, this sample is RANDOM.

Amy is doing a science experiment on how a certain bacterium reacts to an antibiotic. She has 3 dishes of identical bacterium samples with 20 bacteria in each dish. She gives an antibiotic to all of the bacteria in one dish. All of the treated bacteria died, and the bacteria in the other two dishes survived. Identify the sample size in the situation above. A. 40 B. 3 C. 60 D. 20

D. 20

The students at Jillian and Kayla's school will be voting next week to select the theme for the next school dance. Jillian and Kayla have been asked by the student council to survey random groups of students to predict the outcome of the vote. They each randomly selected 40 students and asked which theme was preferred. The results of the surveys are given below. Under the Sea Tropical Islands The Wild West Dragons and Castles Jillian's Survey 11 8 6 15 Kayla's Survey 14 9 4 13 Complete the statements to make them true. "Dragons and Castles" is predicted by to be the winning theme when the whole school votes. Both surveys predict that will receive the fewest votes from the overall student population. Using larger samples would predictors of which theme will win the school-wide vote.

"Dragons and Castles" is predicted by only Jillian's Survey to be the winning theme when the whole school votes. Both surveys predict that 'The Wild West' will receive the fewest votes from the overall student population. Using larger samples would make the surveys more accurate predictors of which theme will win the school-wide vote.

In one day, 6,397 families visited a theme park. Tori asked eight random families the amount that they spent and recorded the information in the table below. Theme Park Spending Family Amount Spent ($) 1 242 2 116 3 176 4 242 5 77 6 242 7 77 8 176 Assuming that the sample was representative of the daily amount spent by all the families, what was the mean daily amount spent at the park?

$168.50

Mr. Bright's middle school math class is attempting to determine the mean number of desks in classrooms at the middle school. He placed each student in one of three groups, and each group was expected to develop their own sampling method and provide a conclusion for the population based on the data they collected. The table below demonstrates the methods and conclusions that each group made. For each survey method, determine whether the conclusion is valid or not by selecting the correct option in each row. Randomly select a hallway, then count the desks in each classroom in the hallway. Mean = 18 Desks Valid Not Valid Randomly select classrooms from a roster of all classrooms in the building, then count the number of desks in each selected classroom. Mean = 22 Desks Valid Not Valid Randomly select students in the cafeteria and poll them as to the number of desks in their homeroom. Mean = 21 Desks Valid Not Valid

*Not Valid *Valid *Not Valid

Chris is taking a trip to a certain town and wants to know what the residents of the town think about the restaurants there. It would not be possible to ask all 500 residents, so Chris plans on surveying a random sample of 50 residents in the population. Select the survey methods that would result in Chris obtaining a random sample. *Surveying every 10th woman and every 10th man at a local diner. *Surveying every 10th woman and every 10th man from a list of people living in the town. *Surveying one person from every 10th home in the town. *Surveying the first 50 people he saw at the airport as he got off the plane. *Surveying the first 25 women and 25 men he met at a grocery store.

*Surveying every 10th woman and every 10th man from a list of people living in the town. *Surveying one person from every 10th home in the town.

Four student candidates are running for the position of president of the 8th grade class. Sarah and James are assigned to cover the election for the school newspaper. Each decides to do some polling and randomly selects 50 8th graders to poll and ask which candidate they supported. The results of the surveys are given below. Candidate A Candidate B Candidate C Candidate D Sarah's Survey 10 9 18 13 James' Survey 11 8 12 19 Select all true statements. *To get a better idea which candidate will win the election, the samples should be larger. *To get a better idea which candidate will win the election, the samples should be smaller. *Both samples predict that, in the election, candidate B will receive the least number of votes. *Both samples predict that candidate D will win the election. *Both samples predict that candidate C will win the election.

*To get a better idea which candidate will win the election, the samples should be larger. *Both samples predict that, in the election, candidate B will receive the least number of votes.

A warehouse had 1,536 bags of flour. A health inspector randomly chose 15 of the bags and found the following number of weevils in them. 25, 19, 27, 19, 31, 25, 19, 33, 31, 25, 19, 33, 27, 19, 27 Assuming that the sample was representative of all of the bags in the warehouse, what was the mode of the number of weevils in a bag? A. 25.27 B. 25 C. 33 D. 19

D. 19

A survey was conducted in two different towns, Town A and Town B, to find the number of vehicles owned by each household. Each town had a total of 4,000 households. The survey was conducted by randomly selecting a group of 200 households from each town. The results obtained are given in the table shown below. Number of Vehicles Town A Town B One 64 66 Two 79 79 Three 36 27 None 21 28 Which of the following statements about the data above is true? A. The estimated number of households with two vehicles is the same for both towns. B. The estimated number of households with three vehicles is the same for both towns. C. The estimated number of households with two vehicles is higher in Town B than Town A. D. The estimated number of households with two vehicles is higher in Town A than Town B.

A. The estimated number of households with two vehicles is the same for both towns.

A small town with a population of 1,200 residents held elections for the position of mayor. Four candidates had announced their candidature for the election. On the day of the election, a local newspaper conducted an exit poll near two polling booths with two groups of 100 residents each. The results are given in the table shown below. Name Group A Group B Chris Jones 51 29 Patrick Smith 6 4 Michael Small 30 54 Susan Davis 13 13 Which of the following statements about the data above is true? A. The estimated number of residents who would have voted for Michael Small is higher for Group B than Group A. B. The estimates for both groups show an equal number of residents would have voted for Michael Small. C. The estimated number of residents who would have voted for Michael Small is higher for Group A than Group B. D. The estimated number of residents who would have voted for Susan Davis is higher for Group A than Group B.

A. The estimated number of residents who would have voted for Michael Small is higher for Group B than Group A.

Amy is doing a science experiment on how a certain bacterium reacts to an antibiotic. She has 3 dishes of identical bacterium samples with 16 bacteria in each dish. She gives an antibiotic to all of the bacteria in one dish. All of the treated bacteria died, and the bacteria in the other two dishes survived. Identify the sample in the situation above. A. all the bacteria in the treated dish B. the antibiotic C. all the bacteria in all 3 dishes D. all bacteria everywhere

A. all the bacteria in the treated dish

Bill stood outside the mall and asked every fourth person to enter the mall for their favorite sport. There were four choices: football, baseball, basketball, and other. Bill surveyed a total of 53 people. Of those surveyed, 14 said football is their favorite, 14 said baseball is their favorite, 13 said basketball is their favorite, and 12 said other. Identify the sample in the situation above. A. every fourth person entering the mall B. everyone who likes football C. everyone who likes basketball D. everyone entering the mall

A. every fourth person entering the mall

A travel agency created a pamphlet for a city. They chose the high temperature for 10 random days during the year to calculate the temperature for the entire year, as shown below. 62°F, 78°F, 80°F, 58°F, 80°F, 62°F, 78°F, 62°F, 80°F, 58°F Assuming that the sample was representative of the daily temperature for the entire year, what was the mean daily temperature? A. 69.5°F B. 69.8°F C. 71.3°F D. 78°F

B. 69.8°F

A city council conducted a survey on speed bumps to see what residents preferred. The council asked every resident in one particular neighborhood what his or her preferences were. Were the results of the city council's survey valid? A. No, because neighborhoods do not have speed bumps. B. No, because the sample was not random. C. Yes, because the neighborhood surveyed wanted speed bumps. D. Yes, because every resident in a neighborhood was surveyed.

B. No, because the sample was not random.

A survey was carried out to find the favorite beverage of a particular telemarketing company having 2,000 employees. To carry out this survey, two groups of 100 employees each were randomly selected and asked to vote for their favorite beverage. The results obtained are given in the table shown below. Beverage Group A Group B Coffee 42 44 Green Tea 9 11 Soft Drinks 28 22 Energy Drinks 21 23 Which of the following statements about the data above is true? A. The estimated number of employees who would have voted for green tea is higher when based on the results of Group A rather than Group B. B. The estimated number of employees who would have voted for coffee is higher when based on the results of Group B rather than Group A. C. The estimates for both groups show an equal number of employees would have voted for coffee. D. The estimated number of employees who would have voted for coffee is higher when based on the results of Group A rather than Group B.

B. The estimated number of employees who would have voted for coffee is higher when based on the results of Group B rather than Group A.

An airplane company flies 44 airplanes daily. The CEO collects the following passenger counts for a random sample of airplanes from the fleet, as shown below. 116, 148, 154, 92, 154, 116, 148, 116, 154, 92 Assuming that the sample is representative of the entire fleet of airplanes, what would be the mean daily passenger count per plane? A. 132 B. 127.5 C. 129 D. 138.2

C. 129

An environmentalist was investigating the impact of a chemical spill on the minnow population in a lake. He randomly caught and released 16 minnows, counting the number of missing scales on the fish, as shown below. 4, 3, 11, 4, 8, 6, 8, 11, 4, 3, 4, 6, 8, 11, 6, 4 Assuming that the sample was representative of the entire population in the lake, what was the mean number of missing scales on a minnow? A. 6.375 B. 4 C. 6.3125 D. 6.4

C. 6.3125

Mike conducted a survey in a movie rental store to find out which is the most popular type of movie at the store. He randomly selected 25 customers in the action movie section for his survey. The results of the survey showed that the most popular type of movie is action movies, followed by comedies, and then dramas. Therefore, Mike concluded that action movies are the most popular type of movies across the store. Select the statement that is true about Mike's conclusion. A. Mike's conclusion was valid because the sample was random. B. Mike's conclusion was valid because the sample was random since all of the people surveyed were in the action movies section of the store. C. Mike's conclusion was not valid because the sample was biased since all of the people surveyed were in the action movies section of the store. D. Mike's conclusion was not valid because the sample was biased since all of the people surveyed were in the comedy movies section of the store.

C. Mike's conclusion was not valid because the sample was biased since all of the people surveyed were in the action movies section of the store.

Which of these is an example of a random sample? A. At a team owners meeting, three people are surveyed to determine the percent of the population who enjoy basketball. B. One of the three best basketball players on a team are randomly chosen for a basketball shoot-out. C. Three audience members are randomly chosen to participate in a halftime shoot-out at a basketball game. D. A sports store asks customers whether or not they enjoy basketball.

C. Three audience members are randomly chosen to participate in a halftime shoot-out at a basketball game.

Arianna wants to know if residents of her town plan to exercise regularly this year. She polled 79 residents of the town who are not members of the local fitness club. She found that 17 of the surveyed residents plan to exercise regularly this year. Is there a sampling bias in the situation above? A. No. Arianna eliminated bias by excluding residents who are members of the local fitness club. B. Yes. Arianna created bias by only polling 79 residents. C. Yes. Arianna created bias by excluding residents who are members of the local fitness club. D. No. Arianna eliminated bias by polling 79 residents.

C. Yes. Arianna created bias by excluding residents who are members of the local fitness club.

A random sample of 80 customers of a department store were surveyed. Using the data collected, which of the following generalizations is valid? A. Question: Do you prefer self-service or cashiered checkout lines? Self-Service Cashiered 29 51 Generalization: More than half of customers prefer self-service checkout lines. B. Question: How do you make most of your clothing purchases? Online In Store Catalog 24 47 9 Generalization: Most customers generally prefer to buy clothing online or from a catalog. C. Question: What type of frequent shopper reward do you prefer most? Cash Back Coupons Valet Parking 45 28 7 Generalization: Twice as many customers prefer cash back than coupons and valet parking combined. D. Question: How many times in a month, on average, do you use a gift card to pay for your purchases? None 1 or 2 3 or 4 More than 4 12 43 15 10 Generalization: Most customers, on average, use a gift card to pay for their purchases fewer than three times a month.

D. Question: How many times in a month, on average, do you use a gift card to pay for your purchases? None 1 or 2 3 or 4 More than 4 12 43 15 10 Generalization: Most customers, on average, use a gift card to pay for their purchases fewer than three times a month.

Susie wants to determine the percentage of people in the United States that have a college degree. She conducts an email survey of 150 people randomly selecting three people from each state. Seventy-five of the people surveyed have a college degree. Based on the survey, Susie concluded that 50% of the people in the United States have a college degree. Select the statement that is true about Susie's conclusion. A. Susie's conclusion is not valid because the sample was biased since all the people were from one state. B. Susie's conclusion is not valid because the sample was random. C. Susie's conclusion is valid because the sample was biased since all the people were from one state. D. Susie's conclusion is valid because the sample was random.

D. Susie's conclusion is valid because the sample was random.

Golf Federation wants to find out which brand of golf balls are the most popular among men living in the United States between the ages of 25 and 40. They surveyed 100 of their male customers living in California between the ages of 25 and 40. The Golf Federation and found that the most popular golf ball is Miller followed by Smith and Sixon. Therefore, the Golf Federation concludes that the most popular brand of golf balls among men living in the United States between the ages of 25 and 40 is Miller. Select the statement that is true about Golf Federation's conclusion. A. The Golf Federation's conclusion was valid because the sample was random. B. The Golf Federation's conclusion was not valid because the sample was biased since all the male customers were of ages from 25 and 40. C. The Golf Federation's conclusion was valid because the sample was biased since the male customers all lived in California. D. The Golf Federation's conclusion was not valid because the sample was biased since the male customers all lived in California.

D. The Golf Federation's conclusion was not valid because the sample was biased since the male customers all lived in California.

The librarian in a local library wants to know the types of books children at his library prefer to read. He surveys every fourth child entering the library about the types of books they prefer to read. Of the 20 children surveyed, 6 children prefer science fiction, 9 children prefer mystery, and 5 children prefer non-fiction. Identify the population in the situation above. A. all children who prefer science fiction books B. every fourth child C. all children who like to read D. all children entering the library

D. all children entering the library

Mrs. Robinson wants to know which type of vacation the students in her school prefer. In her first period class, she surveys the 25 students about their favorite vacation type. Of the students surveyed, 8 preferred trips to the beach, 10 preferred camping trips, and 7 preferred trips to amusement parks. Identify the sample in the situation above. A. all the students in the school B. all the students who prefer trips to the beach C. all the students who like vacations D. all the students in Mrs.Robinson's first period class

D. all the students in Mrs.Robinson's first period class

Jenifer conducted a survey to find out what percentage of households across the city has a home theater system. She randomly called 200 households and found that 140 households have a home theater system. Based on the results, Jenifer concluded that 70% of households in the city have a home theater system. Select the statement that is true about Jenifer's conclusion.

Jenifer's conclusion is valid because the sample was random.

At a sporting goods store, Rebecca randomly selected women's and men's tennis shoes and recorded their prices. The tables below show the data she recorded, in dollars. Women's Tennis Shoe Prices Men's Tennis Shoe Prices 123 77 98 112 72 99 86 133 69 91 57 119 89 105 128 141 65 82 75 139 97 153 120 68 129 132 169 88 92 172 175 108 162 135 83 79 137 164 142 115 Determine which statements are, or are not, strongly supported by the data. []The majority of men's shoes cost more than $100. []The median cost of the women's shoes is $36 less than the median cost of the men's shoes. []The majority of women's shoes cost more than $100. []The mean cost of the men's shoes is $30 more than the mean cost of the women's shoes.

Strongly supported data []The median cost of the women's shoes is $36 less than the median cost of the men's shoes. []The majority of men's shoes cost more than $100. Not Strongly supported data []The majority of women's shoes cost more than $100. []The mean cost of the men's shoes is $30 more than the mean cost of the women's shoes.

Which term describes the group surveyed in each situation? Situation Group Surveyed Brittany wants to know what percentage of the school band take private lessons. She surveys all 40 members of the school band. population sample Alan wants to know what percentage of teachers at his school have children. He surveys all 12 math teachers at his school. population sample James wants to know what percentage of a grocery store's customers use coupons. He surveys all 88 customers who entered the store between 4 PM and 5 PM yesterday afternoon. population sample Gina wants to know what percentage of students in her science class bring lunch from home. She surveyed all 22 students in her class as they entered the classroom yesterday. population sample

[population] [sample] [sample] [population]

Selma wants to know if seventh grade students prefer to do their math homework in silence or with background music. She polled the 27 students in her music class. Nine students preferred to do their math homework in silence, and eighteen students preferred to do their math homework with background music. Identify the sample in the situation above.

students in Selma's music class