In a marketing survey, a random sample of 1001 supermarket shoppers revealed that 273 always stock up on an item when they find that item at a real bargain price.
(a) Let p represent the proportion of all supermarket shoppers who always stock up on an item when they find a real bargain. Find a point estimate for p.
(b) Find a 95% confidence interval for p. Give a brief explanation of the meaning of the interval.
(c) As a news writer, how would you report the survey results on the percentage of supermarket shoppers who stock up on bargain items? What is the margin of error based on a 95% confidence interval?