Respuesta :
Answer:
The margin of error is of 0.01.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.7}{2} = 0.15[/tex]
Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.15 = 0.85[/tex], so Z = 1.037.
The margin of error is of:
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Standard deviation was 0.21.
This means that [tex]\sigma = 0.21[/tex]
Sample of 450:
This means that [tex]n = 450[/tex]
What is the margin of error, assuming a 70% confidence level, to the nearest hundredth?
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]M = 1.037\frac{0.21}{\sqrt{450}}[/tex]
[tex]M = 0.01[/tex]
The margin of error is of 0.01.
