7-1 Populations and Samples

A national burger company sent a survey to its customers. The survey asked about the quality of the burgers and side items that the company sold. Of the 2,200 customers who received the survey, 1,292 replied. Which statement is the best generalization about the survey results?

• Those customers who thought the quality of the side items was poor most likely felt the quality of the burgers was poor as well.

• Not enough customers replied for the company to have accurate survey results.

• Too many people replied to the survey and so skewed the data.

• Enough customers replied for the company to have accurate survey results.

The drama club wants to estimate the number of students who will attend the school play. The president of the club asks 20 of her friends if they are going to the play. She learns that 13 of them plan to attend the play. What could the president do to make it more likely that her estimate will be closer to the actual number of students who attend the play?

• ask 20 more of her friends if they are going to the play

• ask every 20th student on a list of all the students in the school if they are going to the play

• ask the members of the drama club to each ask 20 of their friends if they are going to the play

Mackenzie is organizing a school dance and wants to conduct a survey to determine the theme of the dance. Which method would provide a fair sample of the population?

• Asking every 8th person walking into PE class.

• Asking every 9th person as they get off the bus.

• Asking every 15th person as they walk into a school assembly.

• Asking her entire 6th period class.

A survey was carried out among students in a middle school to decide whether to buy a new set of instruments for the marching band or build a second scoreboard for the football field. Which survey method will best represent the views of the entire school?

• ask 50 students whose names are randomly picked from the school register

• ask all students who attended the last school football game

• ask 40 randomly chosen students who signed up for music class this year

• Ask only those students who don't play football and are not in band.

An airline employee wants to survey some passengers on a large jet carrying 210 people. Which sampling method is the most likely to be random?

• Ask every person who appears to be over 65.

• Ask every person with a child.

• Ask every 9th person boarding the plane.

• Ask every person who sits near a window.

A hospital wants to conduct a survey to find out what patients think about the quality of medical services provided by its doctors and staff. Which of these samples would give it the best results?

• taking the opinion of every fifth patient who is discharged from the hospital

• taking the opinion of patients in the cardiology wing of the hospital

• taking the opinion of the entire staff in the hospital

An amusement park employee was surveying people waiting in line to ride a roller coaster. Each person was asked whether waiting in line was worth their time. Which statement BEST explains why the significance of the survey results might be misinterpreted?

• People could be waiting in the wrong line.

• People could be waiting in line for a short period of time.

• People waiting in line have already shown a willingness to wait.

Paul is conducting a survey in his town to determine which candidates for mayor people intend to vote for in the next election. Which guideline should he follow in deciding on the size of the survey sample?

• The size of the survey sample should be greater than the entire target population.

• The ratio of the sample size to the population should be as great as possible.

• The size of the survey sample should be identical to the entire target population.

Mrs. Cruz is conducting a survey to find out the favorite snack of fifth and sixth graders. She will ask a sample of 100 students. Which of the groups below should be surveyed to get the BEST representative sample?

• 100 students at the movie theater

• the first 100 students who go to a local baseball game

• 20 students from each of the 5 local fifth and sixth grade schools

A student surveyed 100 people and found that 94 out of the 100 people surveyed enjoy exercising. Which statement is the best explanation for these results?

• The people surveyed were eating at a restaurant near an exercise facility. 

• The people surveyed recently saw a television program about the benefits of exercising.

• The people surveyed were entering or exiting an exercise facility.