Margin of Error for Proportions

A survey was given to a random sample of voters in the United States to ask about their preference for a presidential candidate. The percentage of people who said they preferred Candidate A was 66%. The margin of error for the survey was 5%. Which of the following is a reasonable value for the actual percentage of the population that prefers Candidate A?

• 59.6%

• 72.9%

• 60%

• 70.8%

A survey was given to a random sample of voters in the United States to ask about their preference for a presidential candidate. The survey reported a confidence interval that between 30.5% and 35.5% of the population preferred Candidate A. What is the margin of error on the survey? Do not write ± on the margin of error.

A survey was given to a random sample of voters in the United States to ask about their preference for a presidential candidate. The percentage of people who said they preferred Candidate A was 20%. The margin of error for the survey was 3.5%. Which of the following is a reasonable value for the actual percentage of the population that prefers Candidate A?

• 24.5%

• 14.9%

• 17.9%

• 24%

A survey was given to a random sample of voters in the United States to ask about their preference for a presidential candidate. The percentage of people who said they preferred Candidate A was 55%. The margin of error for the survey was 4.5%. Which of the following is not a reasonable value for the actual percentage of the population that prefers Candidate A?

• 51.3%

• 58.2%

• 57.5%

• 48.7%

A study was commissioned to find the mean weight of the residents in certain town. The study found the mean weight to be 156 pounds with a margin of error of 6 pounds. Which of the following is not a reasonable value for the true mean weight of the residents of the town?

• 159.5

• 148

• 161.2

• 151.5

A survey was given to a random sample of voters in the United States to ask about their preference for a presidential candidate. The percentage of people who said they preferred Candidate A was 73%. The margin of error for the survey was 4%. Which of the following is a reasonable value for the actual percentage of the population that prefers Candidate A?

• 67.5%

• 77.7%

• 78.8%

• 69.7%

A study was commissioned to find the mean weight of the residents in certain town. The study found the mean weight to be 198 pounds with a margin of error of 9 pounds. Which of the following is a reasonable value for the true mean weight of the residents of the town?

• 190.5

• 211.1

• 207.8

• 187.5