Hoping to lure more shoppers downtown, a city builds a new public parking garage in the central business district. The city plans to pay for the structure through parking fees. During a two-month period (44 weekdays), daily fees collected averaged $126 with a standard deviation of $15. Required:
a. Are the assumptions you must make in order to use these statistics for inference satisfied?
b. What assumptions must you make in order to use these statistics for inference?
c. Write a 90% confidence interval for the mean daily income this parking garage will generate.
d. Interpret this confidence interval in context.
e. Explain what "90% confidence" means in this context.
f. The consultant who advised the city on this project predicted that parking revenues would average $130 per day. Based on your confidence interval, do you think the consultant was correct? Why?