Question: Estimating Theme Park Attendance. Each year, billions of dollars are spent at theme parks owned by Disney, Universal Studios, Sea World, Busch Gardens, and others. A survey includes 111 people who took trips that included visits to theme parks, and there were 1122 other respondents who took trips without visits to theme parks (based on data from the Travel Industry Association of America).

a. Find the point estimate of the percentage of people who visit a theme park when they visit.

b. Find a 95% confidence interval estimate of the percentage of all people who visit a theme park when they take a trip.

c. The survey was conducted among people who took trips, but no information was given about the percentage of adults who take a pleasure trip in a year, how many people must you survey if you want to be 99% confident that your sample percentage is within 2.5 percentage points of the correct population percentage?