Determine the sample size n needed to construct a 95 confide

Determine the sample size n needed to construct a 95% confidence interval to estimate the population proportion when p overbar p =0.65 and the margin of error equals 6%.

n=? (round to nearest integer)

Solution

Note that      
      
n = z(alpha/2)^2 p (1 - p) / E^2      
      
where      
      
alpha/2 =    0.025  
       
      
Using a table/technology,      
      
z(alpha/2) =    1.959963985  
      
Also,      
      
E =    0.06  
p =    0.65  
      
Thus,      
      
n =    242.758856  
      
Rounding up,      
      
n =    243   [ANSWER]