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A Gallup Poll asked, "What is your favorite Summer Olympics event?" Of the people asked, 27 percent said, "swimming." Here is what Gallup says about the accuracy of this poll:
The results are based on telephone interviews with a sample of 1007 national adults, aged 18 years and older. For results based on the total sample of national adults, one can say with 95 percent confidence that the maximum error attributable to sampling and other random effects is plus or minus 3 percentage points. In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls.
Which of these is a correct confidence statement based on this Gallup Poll, assuming there is no bias?
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