QCEVault

Interval estimates for proportions — Question 150

Original QCE Vault practice · 5 marks

Q150 · Practice questionTechnology-activeComplex unfamiliar5 marks

QUESTION 150 (5 marks)

A pilot survey of 100100 people gives p^=0.24\hat p=0.24. The same estimate is used to plan a final 99% confidence interval with margin of error at most 0.030.03. Using z=2.576z=2.576, determine the minimum final sample size. If the pilot responses may be included in the final sample, determine how many additional responses are required.
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