Question

A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 3% margin of error at a 99% confidence level, what size of sample is needed

Answer 1

1849

Explanation:

Margin of error, E=0.03

Confidence level=0.99

z=2.58

No prior estimate of p is given, so consider p=0.5

Sample size required ,n=2.58^2*0.5*(1-0.5)/0.03^2

n=1849