You drop by your local independent coffee shop on your way to class While standing in line, you notice that 85% of the 20 customers are texting Assume these customers form a reasonably random sample of all potental customers If we tried to make a confidence interval for the proporton of texting customers, which condition would be violated? Choose the correct answer below O A. Success/Failure condition O B. 10% condition OC Randomization condition

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A study is conducted by a physical therapist to determine whether there is a difference in the proportion of men and women in the U.S. that participate in regular sustained physical activity. It is found that 22% of menout of 550 and 19.5% of women out of 450 participated in regular sustained physical activity. Construct a 90% confidence interval for the difference in proportions of men and women that participate in regular sustained and state your conclusion.

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In a study of treatments for very painful​ "cluster" headaches,... Find the 90% confidence interval using technology.

A company has analysed data for a sample of employees who have undertaken training designed to improve their performance in completing a timed task. For each employee in the sample, data shows the time taken to perform the task before training and the time taken post training. The data was used to construct a 95% confidence interval for the mean difference in time taken (before - after), and the interval was (6,10) minutes. Which of the following inferences is correct? Select one: a.The confidence interval indicates that there could be no difference, on average, between the time it takes to perform the task after training and before training. b.We are 95% confident that the time taken to perform the task is lower after training than before training, on average. c.We are 95% confident that the mean reduction in the time taken to perform the task after training is 8 minutes. d.We are 95% confident that everyone doing the training will then be able to perform the task at least 6…

Stanford University conducted a study of whether running is healthy for men and women over age 50. During the first eight years of the study, 1.5% of the 451 members of the 50-plus Fitness Association died. We are interested in the proportion of people over 5o who ran and died in the same eight-year period.   Construct a 95% confidence interval for the population proportion of people over 50 who ran and died in the same eight-year period. Explain in a complete sentence what the confidence interval means

A random sample of 75  customers was polled.   .626 and the 95% confidence interval

The dataset "nurses" is a random sample of 1,000 cases from “Health Care Provider Credential Data” from Washington State Open Data Portal. In the sample, there are 418 CNA's and 278 of the CNA's have expired credentials. Use the statistics from the nurses dataset to answer the following question: "With 90% confidence, what percent of all CNA's on Washington State's healthcare provider list are expired?"