You want to estimate the proportion of customers who are satisfied with their supermarket at $\alpha$ = .10 and within .025 of the true value.It has been estimated that p = .85.How large of a sample is needed?
A)1083
B)553
C)71
D)336

Question

Quizplus · Accepted Answer

To calculate the sample size needed, use the formula for sample size estimation for proportions: n = (Z^2 * p * (1-p)) / E^2, where Z is the Z-score for the confidence level (1.645 for 90%), p is the estimated proportion (0.85), and E is the margin of error (0.025). Plugging in these values gives approximately 553.

You Want to Estimate the Proportion of Customers Who Are α\alphaα

You Want to Estimate the Proportion of Customers Who Are $\alpha$