A researcher wishes to estimate the percentage of adults who support abolishing the penny. What size sample should be obtained if he wishes the estimate to be within 3 percentage points with 95% confidence (a) he uses a previous estimate of 34%? (b) he does not use any prior estimates? Click here to view the standard normal distribution table (page 1), Click here to view the standard normal distribution table (page 2). (a) n= \boxed{} (Round up to the nearest integer.) (b) n= \boxed{} (Round up to the nearest integer.)
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Step 1: Calculate the z-score for a confidence level of 95% using the standard normal distribution table. Show more…
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