7th 6-1 Population and Samples

A bagel shop takes a survey to find the approximate percentage of its customers who prefer the new shop hours. What is the population of this​ survey?

• All of the bagel​ shop's customers

• All bagels sold by the bagel shop

• The customers who were surveyed

• All people in the same town as the bagel shop

During a middle school baseball ​game, every spectator placed his or her ticket stub into a container. After the​ game, the coach chose eight people to march in the sportsmanship parade. What is the sample in this​ situation?

• The coach

• The ticket stubs

• The eight people to march in the sportsmanship parade

• The baseball game spectators

​Trevor's science class is studying the rainfall on the first day of each month for one year. Explain why studying the rainfall on the first day of​ September, October, and November is not a random sample.

• These are three specific months which means other months cannot be selected.

• In these three​ months, the rainfall on the first day of the month is too small to measure.

• These are three consecutive months. Which is a good way to determine rainfall for the year.

• These are three specific months which is too large of a sample to be a random sample.

 To predict the performance of her first period class on their next quiz​, a teacher randomly selects eight students from the class and takes the mean of their scores on the last quiz. Is this sample representative of the​ class's performance on the quiz​? Use pencil and paper. Explain.

• No, because it is a simple random sample.

• ​No, because the students were chosen from the best students in the class.

• Yes, because the students were chosen based on their class average.

• Yes, because it is a simple random sample.

To try to predict the outcome of the vote for the school board election​, a town manager used random numbers to pick 100 registered voters. She then called these voters and asked how they planned to vote. Is the sample taken in this problem representative of the​ population?

• Yes, because it is a simple random sample.

• No, because it does not contain the same number of subjects as the population.

• Yes, because it is a systematic sample.

• Yes, because it contains the same number of subjects as the population.

Matilda recently took a statistics quiz in her math class. In one​ question, 45 of 900 visitors at a local craft show were surveyed about the cost of admission to the show. Matilda incorrectly stated that the sample in this situation was represented by the 900 visitors at the craft show. What was Matilda's mistake?

• The 900 visitors represent a characteristic of the population.

• The 900 visitors represent the population.

• The 900 visitors are not representative.

• The 900 visitors are neither part of the sample nor part of the population.

A movie theater considers upgrading to offer luxury seating. The manager randomly surveys​ 1,200 residents who live within 10 miles of the theater. What is the sample in this​ situation?

• 1,200 randomly surveyed customers of the movie theater

• All of the movie​ theater's customers

• The​ 1,200 residents surveyed

• All residents who live within 10 miles of the theater

You want to study a random sample of 4 out of 26 students in your class. Describe a process you could use to create a random sample with 4 subjects.

• Assign each student a number in alphabetical​ order, then select 4 random numbers.

• Assign each student a​ number, then select students 1 through 4.

• Select 4 students who sit close to you.

• Select the 4 students whose names come first alphabetically.

A population of middle school students consists of 100 boys and 250 girls. If a representative sample from this population contains 20​ boys, how many girls would be expected in this​ sample?

• 8

• 50

• 30

• 60

Your class is studying the number of car commercials on television between 6 P.M. and 8 P.M. for five days. Which of these samples is the best sample for you to​ use?

• The commercials shown between 6 P.M. and 7 P.M. on a randomly chosen day

• The commercials shown between​ 6:30 P.M. and​ 7:30 P.M. on three randomly chosen days

• The first five commercials each of the five days

• The commercials during a random hour between 6pm and 8pm, on a random day.