A human resources manager wishes to estimate the proportion of employees in her large company who have supplemental health insurance. What sample size should she select if she wants 95% confidence and a margin of error of 0.01?
A) 9,604
B) 3,458
C) 6,765
D) 381
E) 4,096

Question

Quizplus · Accepted Answer

To find the sample size required for estimating the proportion of employees with supplemental health insurance, we can use the formula n = (z^2 * p * q) / E^2, where z is the z-score corresponding to the desired confidence level, p is the estimated proportion (use 0.5 if unsure), q = 1 - p, and E is the margin of error. With a 95% confidence level, we have z = 1.96. Assuming an equal proportion (0.5), we get n = (1.96^2 * 0.5 * 0.5) / 0.01^2 = 9604. Therefore, the HR manager should select a sample size of 9,604 employees.

A Human Resources Manager Wishes to Estimate the Proportion of Employees