SOLUTION: A newspaper article about the results of a poll states: "In theory, the results of such a poll, in 99 cases out of 100 should differ by no more than 5 percentage points in either d
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Question 972197: A newspaper article about the results of a poll states: "In theory, the results of such a poll, in 99 cases out of 100 should differ by no more than 5 percentage points in either direction from what would have been obtained by interviewing all voters in the United States." Find the sample size suggested by this statement Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! sample size is a function of the z value and error
error= z/sqrt(n)
error^2=z^2/n
Therefore, n= z^2/error^2
=2.33^2/0.05^2
=2172
For 2 SDs, 100/error rate in % is about the square root of the sample size.
