Lemma
MediumConfidence intervals
OpenStax, Statistics §8.3 A Population Proportion · Exercise 49 · Statistics · Confidence intervals

A Population Proportion · Exercise 49

In a recent poll, 9 of 48 respondents rated the likelihood of a certain event occurring in their community as likely or very likely. Use the plus-four method to create a 97 percent confidence interval for the proportion of American adults who believe that the event is likely or very likely. Explain what this confidence interval means in the context of the problem. A local poll in a New England town found that nine of 48 households think winter-proofing their cars is very important. Use the plus-four method to create a 97 percent confidence interval for the proportion of town residents who think winter-proofing their cars is very important. Explain what this confidence interval means in the context of this scenario.

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OpenStax, Statistics · §8.3 A Population Proportion · Exercise 49

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