1. [-/3 Points] DETAILS ILLOWSKYINTROSTAT1 8.3.064.PR. MY NOTES ASK YOUR TEACHER Marketing companies are interested in knowing the population percent of women who make the majority of household purchasing decisions. Suppose a marketing company did do a survey. They randomly surveyed 200 households and found that in 120 of them, the woman made the majority of the purchasing decisions. We are interested in the population proportion of households where women make the majority of the purchasing decisions. Identify the following. (Enter exact numbers as integers, fractions, or decimals.) (a) X (b) n (c) p' 2. [-/1 Points] DETAILS ILLOWSKYINTROSTAT1 8.3.074.PR. MY NOTES ASK YOUR TEACHER A poll of 1,200 voters asked what the most significant issue was in the upcoming election. Sixty-five percent answered the economy. We are interested in the population proportion of voters who feel the economy is the most important. Define the random variable X in words. the total number of voters the proportion of voters sampled who said the economy is the most important issue in the upcoming election the number of voters who were polled about the upcoming election O the number of voters who said the economy is the most important issue in the upcoming election O the total number of voters in the sample 3. [-/1 Points] DETAILS ILLOWSKYINTROSTAT1 8.3.078.PR. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A poll of 1,200 voters asked what the most significant issue was in the upcoming election. Sixty-five percent answered the economy. We are interested in the population proportion of voters who feel the economy is the most important. What would happen to the confidence interval if the level of confidence were changed from 90% to 95%? The confidence interval would become narrower because it would have to account for more variation. The confidence interval would become wider because it would have to account for less variation. The confidence interval would become narrower because it would have to account for less variation. O The confidence interval would become wider because it would have to account for more variation. There would be no change. 4. [-/1 Points] DETAILS ILLOWSKYINTROSTAT1 8.3.127.HW.GENERAL. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER According to a poll, 83% of California adults (421 out of 506 surveyed) feel that education is one of the top issues facing California. We wish to construct a 90% confidence interval for the true proportion of California adults who feel that education is one of the top issues facing California. Find the error bound. (Round your answer to three decimal places.) 5. [-/2 Points] DETAILS ILLOWSKYINTROSTAT1 8.3.128.HW. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Five hundred fourteen (514) homes in a certain southern California community are randomly surveyed to determine if they meet minimal earthquake preparedness recommendations. One hundred seventy-seven (177) of the homes surveyed met the minimum recommendations for earthquake preparedness and 337 did not. Find the confidence interval at the 90% confidence level for the true population proportion of southern California community homes meeting at least the minimum recommendations for earthquake preparedness. (Round your answers to three decimal places.) 6. [-/1 Points] DETAILS ILLOWSKYINTROSTAT1 8.3.129.HW. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Five hundred seventeen (517) homes in a certain southern California community are randomly surveyed to determine if they meet minimal earthquake preparedness recommendations. One hundred seventy-three (173) of the homes surveyed met the minimum recommendations for earthquake preparedness and 344 did not. Find the point estimate for the population proportion of homes that do not meet the minimum recommendations for earthquake preparedness. (Round your answer to four decimal places.) 7. [-/1 Points] DETAILS BBUNDERSTAT12 7.3.001. For a binomial experiment with r successes out of n trials, what value do we use as a point estimate for the probability of success p on a single trial? p = 8. [-/1 Points] DETAILS BBUNDERSTAT12 7.3.002. In order to use a normal distribution to compute confidence intervals for p, what conditions on np and no need to be satisfied? O np > 5; nq < 5 np> 5; ng > 5 O np < 5; nq < 5 O np < 5; ng > 5 MY NOTES ASK YOUR TEACHER MY NOTES ASK YOUR TEACHER 9. [-/2 Points] DETAILS BBUNDERSTAT12 7.3.003. Results of a poll of a random sample of 3003 American adults showed that 20% do not know that caffeine contributes to dehydration. The poll was conducted for the Nutrition Information Center and had a margin of error of 1.4%. (a) Does the margin of error take into account any problems with the wording of the survey question, interviewer errors, bias from sequence of questions, and so forth? ---Select-- V (b) What does the margin of error reflect? O The margin of error reflects the total length of a confidence interval. O The margin of error reflects the difference between p and p. The margin of error reflects the difference between p and . The margin of error reflects the difference between p and q. 10. [-/7 Points] DETAILS BBUNDERSTAT12 7.3.011.EP.S. For this problem, carry at least four digits after the decimal in your calculations. Answers may vary slightly due to rounding. In a random sample of 67 professional actors, it was found that 36 were extroverts. USE SALT (a) Let p represent the proportion of all actors who are extroverts. Find point estimates for p and q. (Round your answer to four decimal places.) p = q = (b) Find 95% confidence interval for p. Find the maximal margin of error. (Round your answer to two decimal places.) E= Report the bounds from the 95% confidence interval for p. (Round your answers to two decimal places.) lower limit upper limit Give a brief interpretation of the meaning of the confidence interval you have found. We are 95% confident that the true proportion of actors who are extroverts falls within this interval. We are 5% confident that the true proportion of actors who are extroverts falls within this interval. We are 95% confident that the true proportion of actors who are extroverts falls outside this interval. We are 5% confident that the true proportion of actors who are extroverts falls above this interval. (c) Do you think the conditions np > 5 and nq > 5 are satisfied in this problem? Explain why this would be an important consideration. No, the conditions are not satisfied. This is important because it allows us to say that p is approximately normal. No, the conditions are not satisfied. This is important because it allows us to say that p is approximately binomial. Yes, the conditions are satisfied. This is important because it allows us to say that p is approximately binomial. Yes, the conditions are satisfied. This is important because it allows us to say that p is approximately normal. Need Help? Watch It 11. [-/5 Points] DETAILS BBUNDERSTAT12 7.3.012.MI.S. For this problem, carry at least four digits after the decimal in your calculations. Answers may vary slightly due to rounding. In a random sample of 536 judges, it was found that 275 were introverts. USE SALT (a) Let p represent the proportion of all judges who are introverts. Find a point estimate for p. (Round your answer to four decimal places.) (b) Find a 99% confidence interval for p. (Round your answers to two decimal places.) lower limit upper limit Give a brief interpretation of the meaning of the confidence interval you have found. We are 1% confident that the true proportion of judges who are introverts falls within this interval. We are 99% confident that the true proportion of judges who are introverts falls outside this interval. We are 1% confident that the true proportion of judges who are introverts falls above this interval. We are 99% confident that the true proportion of judges who are introverts falls within this interval. (c) Do you think the conditions np > 5 and ng > 5 are satisfied in this problem? Explain why this would be an important consideration. No, the conditions are not satisfied. This is important because it allows us to say that p is approximately binomial. No, the conditions are not satisfied. This is important because it allows us to say that is approximately normal. Yes, the conditions are satisfied. This is important because it allows us to say that p is approximately binomial. Yes, the conditions are satisfied. This is important because it allows us to say that p is approximately normal. Need Help? Master It 13. [-/6 Points] DETAILS BBUNDERSTAT12 7.3.018.S. A random sample of 320 medical doctors showed that 162 had a solo practice. USE SALT (a) Let p represent the proportion of all medical doctors who have a solo practice. Find a point estimate for p. (Use 3 decimal places.) (b) Find a 99% confidence interval for p. (Use 3 decimal places.) lower limit upper limit Give a brief explanation of the meaning of the interval. 99% of the confidence intervals created using this method would include the true proportion of physicians with solo practices. 1% of the all confidence intervals would include the true proportion of physicians with solo practices. 99% of the all confidence intervals would include the true proportion of physicians with solo practices. 1% of the confidence intervals created using this method would include the true proportion of physicians with solo practices. (c) As a news writer, how would you report the survey results regarding the percentage of medical doctors in solo practice? Report p. Report the margin of error. Report the confidence interval. Report p along with the margin of error. What is the margin of error based on a 99% confidence interval? (Use 3 decimal places.)