Reference no: EM131008803
1. As in Exercise 9, you want to estimate the proportion of traditional college students on your campus who own their own car. However, from some research on other college campuses, you believe the proportion will be near 20%.
a) What sample size is needed if you wish to be 95% confi- dent that your estimate is within 0.02 of the true proportion?
b) What sample size is needed if you wish to be 99% confi- dent that your estimate is within 0.02 of the true proportion?
c) What sample size is needed if you wish to be 95% confi- dent that your estimate is within 0.05 of the true proportion?
2. It's believed that as many as 25% of adults over age 50 never graduated from high school. We wish to see if this percentage is the same among the 25 to 30 age group.
a) How many of this younger age group must we survey in order to estimate the proportion of nongrads to within 6% with 90% confidence?
b) Suppose we want to cut the margin of error to 4%. What's the necessary sample size?
c) What sample size would produce a margin of error of 3%?
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Problem regarding the mn ore conditions
: Consider each situation described below. Identify the population and the sample, explain what p and p represent, and tell whether the methods of this chapter can be used to create a confidence interval.
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Problem regarding the margin of error
: A corporate executive reports the re- sults of an employee satisfaction survey, stating that 52% of employees say they are either "satisfied" or "extremely satisfied" with their jobs, and then says "the margin of error is plus or minus 4%." Explai..
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Estimate the percentage of businesses
: In preparing a report on the economy, we need to estimate the percentage of businesses that plan to hire addi- tional employees in the next 60 days.
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Critically evaluate the current policy for the issue
: Discuss a significant issue / challenge arising from globalization that has taken place in the last three to six (3-6) months. Critically evaluate the current policy(ies) for the issue / challenge
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Estimate the proportion of traditional college students
: As in Exercise 9, you want to estimate the proportion of traditional college students on your campus who own their own car. However, from some research on other college campuses, you believe the proportion will be near 20%.
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Estimate the proportion of traditional college
: Suppose you want to estimate the proportion of traditional college students on your campus who own their own car. You have no preconceived idea of what that proportion might be.
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Problem regarding the confidence interval change
: a) How would the confidence interval change if the sample size had been 800 instead of 200? b) How would the confidence interval change if the confidence level had been 90% instead of 95%?
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Coworkers fall in the interval
: From a survey of coworkers you find that 48% of 200 have already received this year's flu vaccine. An approximate 95% confidence interval is (0.409, 0.551). Which of the following are true? If not, explain briefly. a) 95% of the coworkers fall ..
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Standard error of the sample proportion
: a) What is the value of the sample proportion p? b) What is the standard error of the sample proportion?
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