Find the minimum sample size when we want to construct a 90% confidence interval on the population proportion for the support of candidate A in the following mayoral election. Candidate A is facing two opposing candidates. In a preselected poll of 100 residents, 22 supported her. The desired margin of error is 0.08. A: n = 72 B: n = 73 C: n = 103 D: n = 44
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We are given a 90% confidence interval, which means the level of confidence (1 - α) is 0.9. Therefore, α = 0.1, and α/2 = 0.05. Show more…
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