We have calculated a confidence interval based upon a sample of n = 200. Now we want to get a Better estimate with a margin of error only one fifth as large. We need a new sample with
…
A) 450
B) 1000
C) 5000
D) 40

Question

Quizplus · Accepted Answer

To reduce the margin of error to one fifth, the sample size must be increased by a factor of 25 (since the margin of error is inversely proportional to the square root of the sample size). Therefore, the new sample size should be 200 * 25 = 5000.

We Have Calculated a Confidence Interval Based Upon a Sample