# Question

A pizza delivery service delivers to a campus dormitory. Delivery times follow a normal distribution with a mean of 20 minutes and a standard deviation of 4 minutes.

a. What is the probability that a delivery will take between 15 and 25 minutes?

b. The service does not charge for the pizza if delivery takes more than 30 minutes. What is the probability of getting a free pizza from a single order?

c. During final exams, a student plans to order pizza five consecutive evenings. Assume that these delivery times are independent of each other. What is the probability that the student will get at least one free pizza?

d. Find the shortest range of times that includes 40% of all deliveries from this service.

e. For a single delivery, state in which of the following ranges (expressed in minutes) the delivery time is most likely to lie.

18920, 19921, 20922, 21923

f. For a single delivery, state in which of the following ranges (expressed in minutes) the delivery time is least likely to lie.

18920, 19921, 20922, 21923

a. What is the probability that a delivery will take between 15 and 25 minutes?

b. The service does not charge for the pizza if delivery takes more than 30 minutes. What is the probability of getting a free pizza from a single order?

c. During final exams, a student plans to order pizza five consecutive evenings. Assume that these delivery times are independent of each other. What is the probability that the student will get at least one free pizza?

d. Find the shortest range of times that includes 40% of all deliveries from this service.

e. For a single delivery, state in which of the following ranges (expressed in minutes) the delivery time is most likely to lie.

18920, 19921, 20922, 21923

f. For a single delivery, state in which of the following ranges (expressed in minutes) the delivery time is least likely to lie.

18920, 19921, 20922, 21923

## Answer to relevant Questions

A video-rental chain estimates that annual expenditures of members on rentals follow a normal distribution with a mean of $100. It was also found that 10% of all members spend more than $130 in a year. What percentage of ...An ambulance service receives an average of 15 calls per day during the time period 6 p.m. to 6 a.m. for assistance. For any given day what is the probability that fewer than 10 calls will be received during the 12-hour ...Big Nail Construction Inc. is building a large, new student center for a famous Midwestern liberal arts college. During the project Christine Buildumbig, the project manager, requests that a pile of sand weighing between ...Assume that the standard deviation of monthly rents paid by students in a particular town is $40. A random sample of 100 students was taken to estimate the mean monthly rent paid by the whole student population. a. What is ...An English literature course was taken by 250 students. Each member of a random sample of 50 of these students was asked to estimate the amount of time he or she spent on the previous week's assignment. Suppose that the ...Post your question

0