A researcher wishes to? estimate, with 90?% ?confidence, thepopulation proportion of adults who eat fast food four to six timesper week. Her estimate must be accurate within 5?% of thepopulation proportion. ?
(a) No preliminary estimate is available. Find the minimumsample size needed. ?
(b) Find the minimum sample size? needed, using a prior studythat found that 40?% of the respondents said they eat fast foodfour to six times per week. ?
(c) Compare the results from parts? (a) and? (b).
