Determine the sample size required to estimate a population

Determine the sample size required to estimate a population proportion to within 0.08 with 80% confidence and the true value of the population is p=0.5

Solution

Compute Sample Size ( n ) = n=(Z/E)^2*p*(1-p)
Z a/2 at 0.2 is = 1.28
Samle Proportion = 0.5
ME = 0.08
n = ( 1.28 / 0.08 )^2 * 0.5*0.5
= 64 ~ 64