After calculating the sample size needed to estimate a population proportion to within 0.05,you have been told that the maximum allowable error (B)must be reduced to just 0.025.If the original calculation led to a sample size of 1000,the sample size will now have to be
A)2000.
B)4000.
C)1000.
D)8000.

Question

Quizplus · Accepted Answer

The sample size is inversely proportional to the square of the margin of error. Reducing the margin of error by half (from 0.05 to 0.025) requires quadrupling the sample size, so the new sample size is 4000.

After Calculating the Sample Size Needed to Estimate a Population