Answer:
Option D) 340
Step-by-step explanation:
We are given the following in the question:
Alpha, α = 0.05
Population standard deviation, σ = $47
Margin of error = 5
95% Confidence Interval:
[tex]\mu \pm z_{critical}\frac{\sigma}{\sqrt{n}}[/tex]
[tex]\text{Margin of error} = z_{critical}\frac{\sigma}{\sqrt{n}}[/tex]
Putting the values, we get,
[tex]z_{critical}\text{ at}~\alpha_{0.05} = 1.96[/tex]
[tex]5 = 1.96(\dfrac{47}{\sqrt{n}} )\\\\\sqrt{n} = \dfrac{47\times 1.96}{5}\\\\n = 339.443776\\\Rightarrow n \approx 340[/tex]
Thus, the correct answer is
Option D) 340
