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EasyConfidence intervals
OpenStax, Introductory Business Statistics 2e §8.4 Calculating the Sample Size n: Continuous and Binary Random Variables · Example 1 · Statistics · Confidence intervals

Calculating the Sample Size n: Continuous and Binary Random Variables · Example 1

Suppose a mobile phone company wants to determine the percentage of customers who would upgrade to the latest-version smartphone from their current smartphone. How many customers 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 who would upgrade to the latest-version smartphone?

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OpenStax, Introductory Business Statistics 2e · §8.4 Calculating the Sample Size n: Continuous and Binary Random Variables · Example 1

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