Question

In: Statistics and Probability

8. A particular poll tracks daily the percentage of Americans who approve or disapprove of the...

8. A particular poll tracks daily the percentage of Americans who approve or disapprove of the performance by President 1. Daily results are based on random telephone interviews with approximately 1300 national adults. The poll reports that 49% of adults approve of President 1. The same poll reported an approval rating of 50​% for President 2. A news anchor remarks that​ "President 1​ doesn't even get as much approval as President 2​ did." Is there evidence that this difference is​ real? State and test the appropriate hypotheses. Check conditions.

A. What is the value of the test​ statistic? (Round to two decimal places as​ needed.)

9. It the​ 1980s, it was generally believed that congenital abnormalities affected about 8​% of a large​ nation's children. Some people believe that the increase in the number of chemicals in the environment has led to an increase in the incidence of abnormalities. A recent study examined 366 randomly selected children and found that 37 of them showed signs of an abnormality. Is this strong evidence that the risk has​ increased? (Consider a​ P-value of around 0.05 to represent reasonable​ evidence.)

A. What is the​ P-value? (Round to three decimal places as​ needed)

10. A magazine is considering the launch of an online edition. The magazine plans to go ahead only if it is convinced that more than 20​% of current readers would subscribe. The magazine contacted a simple random sample of 500 current​ subscribers, and 108 of those surveyed expressed interest. What should the magazine​ do?

A. What is the​ P-value of the test​ statistic? (Round to three decimal places as​ needed.)

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