Answer: 1.57
Step-by-step explanation:
As we consider the given description, we have
n= 25
[tex]\sigma^2=16\\\\\sigma=4[/tex]
Critical z-value for 95% confidence =[tex]z_{\alpha/2}=1.96[/tex]
The formula to find the margin of error :
[tex]E=z_{\alpha/2}\dfrac{\sigma}{\sqrt{n}}[/tex]
[tex]E=(1.96)\dfrac{4}{\sqrt{25}}\\\\=(1.96)(0.8)\\\\=1.568\approx1.57[/tex]
Hence, the margin of error for a 95% confidence interval =1.57
