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

A Population Proportion · Example 5

Suppose a mobile phone company wants to determine the current percentage of customers ages 50+ who use text messaging on their cell phones. How many customers ages 50+ should the company survey in order to be 90 percent confident that the estimated (sample) proportion is within 3 percentage points of the true population proportion of customers ages 50+ who use text messaging on their cell phones? Assume that p′ = 0.5.

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OpenStax, Statistics · §8.3 A Population Proportion · Example 5

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