Questions: Assume that a sample is used to estimate a population proportion μ. Find the margin of error M.E. that corresponds to a sample of size 57 with a mean of 82.9 and a standard deviation of 19.8 at a confidence level of 99.9%.
Report ME accurate to one decimal place because the sample statistics are presented with this accuracy.
M.E. =
Answer should be obtained without any preliminary rounding. However, the critical value may be rounded to 3 decimal places.
Transcript text: Assume that a sample is used to estimate a population proportion $\mu$. Find the margin of error M.E. that corresponds to a sample of size 57 with a mean of 82.9 and a standard deviation of 19.8 at a confidence level of 99.9\%.
Report ME accurate to one decimal place because the sample statistics are presented with this accuracy.
M.E. = $\square$
Answer should be obtained without any preliminary rounding. However, the critical value may be rounded to 3 decimal places.
Solution
Solution Steps
Step 1: Determine the Z-Score
For a confidence level of \(99.9\%\), the corresponding Z-score is calculated to be \(Z = 3.3\).
Step 2: Calculate the Margin of Error
The formula for the margin of error (M.E.) is given by:
\[
\text{Margin of Error} = \frac{Z \times \sigma}{\sqrt{n}}
\]
Substituting the known values:
\(Z = 3.3\)
\(\sigma = 19.8\)
\(n = 57\)
We can express the calculation as follows:
\[
\text{Margin of Error} = \frac{3.3 \times 19.8}{\sqrt{57}}
\]