Sampling-and-Error-

Which of the following situations could be used to produce an unbiased random sample?


Surveying students in a college psychology class to find out preferred majors of students at that school.

Asking people at the local supermarket what their favorite brand of ice cream is to find out what the preferred brand of ice cream is in that city.

Survey every tenth audience member leaving the American Country Music Awards and ask what their favorite type of music is.

Finding the heights of all 9th grade female students at a high school and using it to determine the average height of all girls at the school.

Which of the following situations would not produce an unbiased random sample?


Send a survey to students at an online private high school to find out how many students use the computer to do school work.

Asking every twentieth person on a list of registered voters to determine which political candidate is favored.

Ask every tenth person in 12th grade at Jacaranda high school to find out the favorite TV show for seniors at that school.

Survey 2 teachers in each subject at Bluefort High School to find out how many had graduate degrees.

Find the margin of error if p = 71% and n = 100. Round to four decimal places.


0.2204

0.0041

0.0848

0.0908

Find the margin of error if p = 65% and n = 500. Round to four decimal places.


0.0427

0.0926

0.0009

0.0414

A poll asked people to name the most serious problem facing the country. forty-three percent of the 900 randomly selected people said crime. What is the margin of error? Round to four decimal places.


0.0165

0.0330

0.0261

0.0523

According to a recent poll, 40% of shoppers planned to spend $1000 or more during a holiday season. The margin of error was 4%. How many people were surveyed?


600

38

1400

1000

One hundred people were asked whether they would vote for Candidate A or Candidate B in an upcoming election. More people said they would vote for Candidate A. How many said they would vote for Candidate A if the margin of error was 8.4%.


92%

8%

77%

23%

Five-hundred ten of 650 high school students said that pizza was their favorite food in the school cafeteria. What is the margin of error? Round to four decimal places.


0.0005

0.0003

0.0161

0.0322

Complete the sentence with the best answer.

When p stays the same but the sample size increases, the Margin of Error ___?___.


increases

decreases

stays the same

all of the above.

In a recent survey 45% of students at a local high school said they love chocolate ice cream. If the margin of error was 4.3%, about how many students were surveyed?


973 students

535 students

133 students

243 students