## Based on Census data, the five-year estimate for number of vehicles per household between 2006 and 2010 is:

11. Question 11 Based on Census data, the five-year estimate for number of vehicles per household between 2006 and 2010 is: Vehicles Available United States Dallas, TX New York City,…

## We have developed a 95% confidence interval for the population the proportion which is [32.2%, 35.8%]. What is the margin of error?

10. Question 10 We have developed a 95% confidence interval for the population the proportion which is [32.2%, 35.8%]. What is the margin of error? 1 point   1.8%  …

## A random sample of graduate students were asked, “Would you come back to school to get a second degree if you were given the opportunity?” Of the 150 people surveyed, 127 of them said that they would do so. Find a 95% confidence interval for the proportion of graduate students who would come back to school (Z_{a/2}Za/2​ = 1.96). Round your answer to three decimal places.

8. Question 8 A random sample of graduate students were asked, “Would you come back to school to get a second degree if you were given the opportunity?” Of the…

## You take a random sample (mean = x̅) from some population and form a 96% confidence interval for the population mean, m. Which value (or notation presenting the value) is guaranteed to be in the confidence interval?

6. Question 6 You take a random sample (mean = x̅) from some population and form a 96% confidence interval for the population mean, m. Which value (or notation presenting…

## A drug company is undertaking a survey study to assess the potential market share for their new drug. They desire to be within 0.1 of the true proportion of the market share. Currently the survey has been sent to 100 physicians. If all 100 respond, would this survey provide the precision they require for a 95% confidence interval?

5. Question 5 A drug company is undertaking a survey study to assess the potential market share for their new drug. They desire to be within 0.1 of the true…

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9. Question 9 The 99% confidence interval for a population proportion is [0.24, 0.86]. What is the sample mean proportion. (Z_{a/2}Za/2​ = 2.58). Choose the closest answer. 1 point  …

## What is the minimum sample size required to provide a 95% confidence interval for a mean if we want to be no more than 1.25 cm off? You may assume that the population is normal with standard deviation of 4 cm. (Z_{a/2}Za/2​ = 1.96)

4. Question 4 What is the minimum sample size required to provide a 95% confidence interval for a mean if we want to be no more than 1.25 cm off?…

## An automobile company wants to determine the average amount of time it takes a machine to assemble a car. A sample of 40 times yielded an average time of 23.92 minutes, with a sample standard deviation of 6.72 minutes. Assuming normality of assembly times, provide a 98% confidence interval for the mean assembly time. Use Z_{a/2}Za/2​ = 2.33 and round your answer to three decimal places.

3. Question 3 An automobile company wants to determine the average amount of time it takes a machine to assemble a car. A sample of 40 times yielded an average…

## Decreasing the sample size while holding the confidence level the same will do what to the width of your confidence interval?

7. Question 7 Decreasing the sample size while holding the confidence level the same will do what to the width of your confidence interval? 1 point   Make it smaller…

## The Z_{a/2}Za/2​ for a 95% confidence level of a confidence interval is 1.96. What does the number 1.96 signify?

2. Question 2 The Z_{a/2}Za/2​ for a 95% confidence level of a confidence interval is 1.96. What does the number 1.96 signify? 1 point   Margin of error   Number…