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OpenStax, Introductory Statistics 2e §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 aged 50+ who use text messaging on their cell phones. How many customers aged 50+ should the company survey in order to be 90% confident that the estimated (sample) proportion is within three percentage points of the true population proportion of customers aged 50+ who use text messaging on their cell phones.

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OpenStax, Introductory Statistics 2e · §8.3 A Population Proportion · Example 5

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