Question

Find the margin error when p=83% and n=300

Answer 1

In absence of specific information , 95% confidence level can be assumed
1) Margin of error = Confidence coefficient*Standard error of p
Confidence coefficient is the critical value of z for 95% confidence level = 1.96
Standard error of p = sqrt [p*(1-p)/n]
= sqrt [0.83*0.17/300]
= 0.0217
Margin of error = 1.96*0.0217 = 0.04