A manufacturer of golf equipment wishes to estimate the number of left-handed golfers. How large a sample is needed in order to be 95% confident that the sample proportion will not differ from the true proportion by
More than 4%? A previous study indicates that the proportion of left-handed golfers is 9%.

Question

Quizplus · Accepted Answer

To estimate the sample size needed for a proportion with a specific margin of error (E), the formula is n = (Z^2 * p * (1-p)) / E^2, where Z is the Z-score for the confidence level (1.96 for 95% confidence), p is the estimated proportion (0.09 for 9%), and E is the margin of error (0.04 for 4%). Plugging in the values: n = (1.96^2 * 0.09 * (1-0.09)) / 0.04^2 ≈ 197.

A Manufacturer of Golf Equipment Wishes to Estimate the Number