A pollster wishes to estimate the number of left-handed scientists. How large a sample is needed in order to be95% confident that the sample proportion will not differ from the true proportion by more than 6%? A previousstudy indicates that the proportion of left-handed scientists is 9%.
A) 88
B) 62
C) 97
D) 27

Question

Quizplus · Accepted Answer

To calculate the sample size needed, we use the formula for sample size in proportion estimation: n = (Z^2 * p * (1-p)) / E^2. Here, Z is the Z-score for 95% confidence (1.96), p is the estimated proportion (0.09), and E is the margin of error (0.06). Plugging in these values gives n ≈ 88.

A Pollster Wishes to Estimate the Number of Left-Handed Scientists