Theme Park Spending In a random sample of 40 visitors to a c

Theme Park Spending In a random sample of 40 visitors to a certain theme park, it was determined that the mean amount of money spent per person at the park (including ticket price) was $93.43 per day with a standard deviation of $15. Construct and interpret a 99% confidence interval for the mean amount spent daily per person at the theme park.

Solution

alpha = 1-0.99 = 0.01

alpha /2 = 0.005

df = 39

T = 2.704

I: 93.43 +/- 2.704 * 15 / srqt(40)

I : 93.43 +/- 6.413

I: [87.017 , 99.843]

we are 99% confident that the mean amount spent daily per person at the theme park is between $87.017 and $99.843