A sample of n = 300 items has been randomly selected. Of these, 55 contain the attribute of interest. Based on this information, compute a 90% confidence intervalestimate for the proportion of items in the population that have this attribute.
Assume that a decision maker wants to estimate a population proportion with 90% confidence and a margin of error of ±0.03. The decision maker has obtained a pilot sample of 10. This pilot sample’s proportion is 0.50. What sample size will be sure to achieve the desired results? How many additional observations must the decision maker obtain?
This solution gives the step-by-step method for computing sample size for estimating population proportion (see attachments).