# a pollster wants to construct a 95% confidence interval for the proportion of adults who believe the economic conditions are getting better.

a pollster wants to construct a 95% confidence interval for the proportion of adults who believe the economic conditions are getting better. A gallup poll taken in July 2010 estimates this proportion to be 0.33. Using this proportion what sample size is needed so that the confidence interval will have a margin of error of 0.015?