Suppose you are planning a sample of employees to determine

Suppose you are planning a sample of employees to determine the monthly average # of vacation days. Standards set: Confidence level of 99% and an error of less than 5 units. Standard deviation be 6 units. What would be the required sample size?

Solution

Given a=1-0.99 = 0.01, Z(0.005) = 2.58 (from standard normal table)

So n=(Z*s/E)^2

=(2.58*6/5)^2

=9.585216

Take n=10