A Clock and Timepiece Boutique manager wants to estimate the proportion of satisfied customers to improve their services. What is the smallest sample size required to obtain a 95\% confidence interval for the proportion of satisfied Clock and Timepiece Boutique customers with a margin of error no more than 0.081? Assume a planning proportion of 0.656. 1) 120 2) 133 3) 147 4) 160
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The formula to calculate the sample size needed for estimating a proportion is: n = (Z^2 * p * (1-p)) / E^2 Where: n = sample size Z = Z-score corresponding to the desired confidence level (for a 95% confidence level, Z = 1.96) p = planning proportion (0.656 in Show more…
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