A researcher is studying the population of a small town of N=3000 people.

#1
A researcher is studying the population of a small town of N=3000 people. She's interested in estimating p for several yes/no questions on a survey. The estimate is to be within E=0.05 of the true proportion.
Q1: If, from the pilot study, the proportion is estimated to be 0.27 and the 90% confidence level is used, what is the minimum sample size required?

Q2: If the 95% confidence level is used, what is the minimum sample size required?
 

Karabiner

TS Contributor
#5
Are these answering options?

The statement "The estimate is to be within E=0.05 of the true proportion.", and using pilot data as population estimate
raise some doubt about the competence of those who created the questions. But anyway, which approach do you suggest?