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 $1,264 with a standard deviation of $150.
(a) What assumptions must you make in order to use these statistics for inference?
(b) Write a 90% confidence interval for the mean daily income this parking garage will generate, rounded appropriately.
(c) The consultant who advised the city on this project predicted that parking revenues would average $1,300 per day. On the basis of your confidence interval, do you think the consultant was correct? Why or why not?
(d) Give a 90% confidence interval for the total revenue earned during five weekdays.