CH 14.6

2.

Datafile:

Number of Customers 5, 2, 4, 4, 6, 3, 7, 3, 8, 4,

Waiting Time (Minutes) 47, 27, 36, 44, 52, 21, 82, 43, 69, 28,

Many small restaurants in Portland, Oregon, and other cities across the United States do not take reservations. Owners say that with smaller capacity, no-shows are costly, and they would rather have their staff focused on customer service rather than maintaining a reservation system.However, it is important to be able to give reasonable estimates of waiting time when customers arrive and put their name on the waiting list. The file RestaurantLine contains 10 observations of number of people in line ahead of a customer (independent variablex) and actual waiting time (in minutes) (dependent variabley). The estimated regression equation is:= 4.35 + 8.81x

andMSE = 94.42.

(a)

Develop a point estimate (in min) for a customer who arrives withsevenpeople on the wait-list. (Round your answer to two decimal places.)

^*=66.02min

this part is correct

(b)

Develop a 95% confidence interval for the mean waiting time (in min) for a customer who arrives withsevencustomers already in line. (Round your answers to two decimal places.)

min to

min

not 58.93 to 73.11

(c)

Develop a 95% prediction interval for Roger and Sherry Davy's waiting time (in min) if there aresevencustomers in line when they arrive. (Round your answers to two decimal places.)

min to

min

not 42.52 to 89.52