SOLUTION: How do I find the sample size of a sample when I am given the Margin of Error? An example is I need to find the sample size when my margin of error is +- 4%.I know the formula for

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Question 396321: How do I find the sample size of a sample when I am given the Margin of Error? An example is I need to find the sample size when my margin of error is +- 4%.I know the formula for finding the margin of error for a sample size, which would be where (N) is the sample size. To get a sample size from the margin of error, which in this case is 4% I tried and I get 4 *10^4. (I put that in scientific notation the best I knew how.) I also tried
I don't know how to get the Sample Size when given the margin of error.
Found 2 solutions by stanbon, BlockiestCherry:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
How do I find the sample size of a sample when I am given the Margin of Error? An example is I need to find the sample size when my margin of error is +- 4%.
ME = zs/sqrt(n)
4 = zs/sqrt(n)
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You would need to know Z and s.
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Cheers,
Stan H.
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I know the formula for finding the margin of error for a sample size, which would be where (N) is the sample size. To get a sample size from the margin of error, which in this case is 4% I tried and I get 4 *10^4. (I put that in scientific notation the best I knew how.) I also tried
I don't know how to get the Sample Size when given the margin of error.

Answer by BlockiestCherry(1) (Show Source):
You can put this solution on YOUR website!
In order to find the sample space of a margin of error for +- 4%, you could say the 4%=.04=1/25. With knowing that 1/25 is equal to 4% you can set it equal to the square root on n. Then take the reciprocals of both sides and you should get then square both sides to get n=625.