AP Stat Confidence Intervals

A survey was given to a random sample of 1750 voters in the United States to ask about their preference for a presidential candidate. Of those surveyed, 595 respondents said that they preferred Candidate A.

What would the critical value for a 99% confidence interval be for this situation?

A study by the department of education of a certain state was trying to determine the mean SAT scores of the graduating high school seniors. The study examined the scores of a random sample of 25 graduating seniors and found the mean score to be 471 with a standard deviation of 83.

What would the critical value for a 98% confidence interval be in this situation?

A study of a local high school with 2,000 students tried to determine the mean number of text messages that each student sent per day. The study surveyed a random sample of 253 students in the high school and found a mean of 186 messages sent per day with a standard deviation of 65 messages. Which conditions for calculating a confidence interval are met in this situation? Check all that are met.

• Random Condition

• 10% Condition

• Normal/Large Sample Condition

A survey was given to a random sample of 55 residents of a town of 30,000 people to determine whether they support a new plan to raise taxes in order to increase education spending. Of those surveyed, 8 respondents said they were in favor of the plan.

Should you use a one sample z interval or a one sample t interval for this problem?

• One Sample z Interval

• One Sample t Interval

A survey was given to a random sample of 55 residents of a town of 30,000 people to determine whether they support a new plan to raise taxes in order to increase education spending. Of those surveyed, 8 respondents said they were in favor of the plan. Which of the following conditions are met for determining a 95% confidence interval? Check all that are met.

• Random Condition

• Large Counts Condition

• 10% Condition

A survey was given to a random sample of 55 residents of a town of 30,000 people to determine whether they support a new plan to raise taxes in order to increase education spending. Of those surveyed, 22 respondents said they were in favor of the plan.

What would be the critical value for a 95% confidence interval?

A study of a large local high school tried to determine the mean amount of money that each student had saved. The study surveyed a random sample of 97 AP students in the high school and found a mean savings of 4100 dollars with a standard deviation of 500 dollars. Would you use a One Sample z Interval or a One Sample t Interval for this situation?

• One Sample z Interval

• One Sample t Interval

A study of a large local high school tried to determine the mean amount of money that each student had saved. The study surveyed a random sample of 97 AP students in the high school and found a mean savings of 4100 dollars with a standard deviation of 500 dollars. Which conditions are met for calculating a confidence interval? Check all that are met.

• Random Condition

• 10% Condition

• Normal/Large Counts Condition

A study of a large local high school tried to determine the mean amount of money that each student had saved. The study surveyed a random sample of 97 AP students in the high school and found a mean savings of 4100 dollars with a standard deviation of 500 dollars. What would be the critical value for a 90% confidence interval in this situation?

A survey was given to a random sample of 1750 voters in the United States to ask about their preference for a presidential candidate. Of those surveyed, 595 respondents said that they preferred Candidate A.

Would you use a one sample z interval or a one sample t interval for this situation?

• One Sample z interval

• One Sample t Interval