Answer:
n ≥ 385
Step-by-step explanation:
Solution:-
- The %error allowed for the estimate of true proportion "p", E = 0.05
- The Confidence Level ( 1 - α ) = 0.95
- The number of employees sampled = n
- Use the look table for Z-critical value corresponding to the significance level "α" = 0.05:
Z-critical = Z-α/2 = Z-0.025
Z-0.025 = 1.96
- Assume the true population to be p = 0.5
- We will use the error formula for estimation of true population proportion:
[tex]E = Z-critical *\sqrt{\frac{p*(1-p)}{n} } \\\\n = (\frac{Z-critical}{E})^2*p*(1-p)\\\\n = (\frac{1.96}{0.05})^2*0.5*(1-0.5)\\\\n = 385[/tex]
Answer: The sample size for employees must be n≥385 to keep the estimation within the margin of 5% error
