(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 95% CI for the population proportion of professional tennis players who earn more than $2 millions a year is found to be [0.82, 0.88]. Given this information the sample size that was used was approximately A) 545 B) 382 C) 233 D) 378

Answer: A) 545

2. Relevant equations

Z = 1.96 for 95% CI

+/- Z[S/sqrt(n)] = 0.03

3. The attempt at a solution

+/- 1.96 [0.03)/sqrt(n) = 0.03

sqrt(n) = 1.96(2)/0.03

sqrt(n) = 130

n = 11.4 <-- this incorrect.

The answer should be A) 545. But where did i go wrong? How do i solve this problem? Thanks.

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# Homework Help: 95% CI for the population proportion

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