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OpenStax, Statistics §8.3 A Population Proportion · Try It 5 · Statistics · Confidence intervals

A Population Proportion · Try It 5

The research group referenced in talked to teens in smaller focus groups but also interviewed additional teens over the phone. When the study was complete, 588 teens had answered the question about their social media site friends, with 159 saying that they have more than 500 friends. Use the plus-four method to find a 90 percent confidence interval for the true proportion of teens who would report having more than 500 online friends based on this larger sample. Compare the results to those in.

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OpenStax, Statistics · §8.3 A Population Proportion · Try It 5

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