Question

Is there a minimum sample size that must be used? What is the minimum sample size? What might be an advantage to collecting a sample larger than the minimum sample size?

p = .4028 n= 72 cl= .95 E= .11329

Answer 1

Solution:

Given that,

= 0.4028

1 - = 1 - 0.4028 = 0.5972

margin of error = E = 0.11329

At 95% confidence level the z is ,

= 1 - 95% = 1 - 0.95 = 0.05

/ 2 = 0.05 / 2 = 0.025

Z_/2 = Z_0.025 = 1.960

Sample size = n = ((Z _{/ 2}) / E)² * * (1 - )

= (1.960 / 0.11329 )² * 0. .4028 * 0.05972

= 71.997

= 72

n = sample size = 72