Final answer:
The margin of error is calculated using the formula for a sample proportion and comes out to be 0.072 when rounded to three decimal places.
Step-by-step explanation:
The student's question pertains to finding the margin of error with a given confidence level and sample proportion. Using the given data, we can calculate the margin of error following the formula:
Margin of Error (E) = z * sqrt((p*(1-p))/n)
Where:
z is the z-value corresponding to the confidence level (2.58 for 99%).
p is the sample proportion (0.68).
n is the sample size (278).
Plugging the numbers into the formula:
E = 2.58 * sqrt((0.68 * (1 - 0.68)) / 278)
Calculating the margin of error:
E = 2.58 * sqrt((0.68 * 0.32) / 278)
E = 2.58 * sqrt(0.2176 / 278)
E = 2.58 * sqrt(0.000782733)
E = 2.58 * 0.0279798619
E = 0.0722095435
Therefore, after rounding to three decimal places, the margin of error is 0.072.