Suppose you want to estimate the proportion of people in your community who would enjoy a dramatic read-aloud of a particular piece of written work. Also suppose previous studies have shown this proportion to be around 0.3.

• a. Determine how many people you would have to sample in order to estimate this proportion to within a margin of error of 0.025 with 90% confidence
• b. If your boss says that this number (your answer to part a) is too large to be practical, you might respond that a smaller sample size would suffice if either the margin-of-error (.025) or the confidence level (90%) were changed.
  • I. In which direction would the margin-of-error need to change in order for a smaller sample size to suffice?
  • II. In which direction would the confidence level need to change in order for a smaller sample size to suffice?