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OpenStax, Statistics §8.3 A Population Proportion · Exercise 37 · Statistics · Confidence intervals

A Population Proportion · Exercise 37

An article regarding dating and marriage recently appeared in a major newspaper. Of the 1,709 randomly selected adults, 315 identified themselves as ethnicity A, 323 identified themselves as ethnicity B, 254 identified themselves as ethnicity C, and 779 identified themselves as ethnicity D. In this survey, 86 percent of ethnicity B said that they would welcome a person of ethnicity A into their families. Among ethnicity C, 77 percent would welcome a person of ethnicity D into their families, 71 percent would welcome a person of ethnicity A, and 66 percent would welcome a person of ethnicity B.

(a) We are interested in finding the 95 percent confidence interval for the percent of all ethnicity B adults who would welcome a person of ethnicity D into their families. Define the random variables X and P′ in words.
(b) Which distribution should you use for this problem? Explain your choice.
(c) Construct a 95 percent confidence interval.
(a) State the confidence interval.
(b) Sketch the graph.
(c) Calculate the error bound.

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OpenStax, Statistics · §8.3 A Population Proportion · Exercise 37

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