Question: A pizza delivery service delivers to a campus dormitory Delivery

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

Sales0
Views103