How large of a sample size is required?

Question

You want to obtain a sample to estimate a population proportion. Based on previous evidence, you believe the population proportion is approximately . You would like to be 98% confident that your esimate is within 2% of the true population proportion. How large of a sample size is required?

n = 

Do not round mid-calculation. However, use a critical value accurate to three decimal places.

Answer 1

n= (z_∝/2 /E)² *p*(1-p)

n= (2.326/0.02)²*0.27*(1-0.27) = 2666