A previous random sample of 4000 U.S. citizens yielded 2250 who are in favor of gun control legislation. How many citizens would need to be sampled for a 95% confidence interval to estimate the true proportion within 2%?
A) 2364
B) 2498
C) 2209
D) 2401

Question

Quizplus · Accepted Answer

The sample size needed for a 95% confidence interval with a margin of error of 2% is 2364. This can be calculated using the formula n = (Z^2 * p * q) / e^2, where Z is the z-score for the desired confidence level (1.96 for 95%), p is the sample proportion (0.5625), q is 1 - p (0.4375), and e is the margin of error (0.02).

A Previous Random Sample of 4000 U