SOLUTION: A research institute poll asked respondents if they felt vulnerable to identify theft. In the poll, n= 1090 and x= 548 who said yes. Use a 99% confidence level. Identify the margin

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Question 1202995: A research institute poll asked respondents if they felt vulnerable to identify theft. In the poll, n= 1090 and x= 548 who said yes. Use a 99% confidence level. Identify the margin of error E.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
n = 1090
x = 548
p = 548 / 1090 = .50275
s = sqrt(.50275 * (1 - .50275) / 1090) = .015144.
critical z at 99% two tailed confidence level = plus or minus 2.5758.
when z = 2.5758, z-score formula becomes 2.5758 = (x - m) / .015144.
solve for (x - m) to get (x - m) = 2.5758 * .01544 = .03901.
that's your margin of error.
your 99% confidence interval is from .50275 - .03901 to .50275 + .03901.
this is equal to from .46374 to .54176.
your solution is that the margin of error = (x - m) = .03901.

here's what the 99% confidence interval looks like on a graph when rounded to 3 decimal places.