PLEASE SHOW EACH AND EVERY STEP! THANK YOU!! Emilio, the owner of Pepe Delgados,
ID: 3209277 • Letter: P
Question
PLEASE SHOW EACH AND EVERY STEP! THANK YOU!!
Emilio, the owner of Pepe Delgados, is interested in taking a more statistical approach to predicting customer load. He begins the process by gathering data on the number of arrivals in five-minute intervals. The data below represent the arrivals in five-intervals between 7:00p ans 8:00p every Saturday for three weeks. Assume that arrivals are Poisson distributed. The questions that follow pertain to the 7:00p to 8:00p time period, (adapted from [Black 2012]) a. Compute lambda using the data from all three weeks as one data set. b. What is the probability that no customers arrive during any five-minute interval? c. What is the probability that six or more customers arrive during any five-minute interval? d. What is the probability that during a 10-minute interval fewer than four customers arrive? e. What is the probability that no customers arrive during any 10-minute interval? Compare with part b. f. What is the probability that exactly eight customers arrive in any 15-minute interval?Explanation / Answer
Solution
Back-up Theory
If X = number of arrivals in a 5-minute interval, follows a Poisson Distribution with parameter , then
P(X = x) = (e-)(x)/(x!),where is the mean arrival rate per 5 minutes……………..(1)
If X = number of arrivals in a 5-minute interval, follows a Poisson Distribution with parameter , and Y = number of arrivals in a 10-minute interval, then
Y follows a Poisson Distribution with parameter 2 [note: 10 = 2x5]………………………………..(2)
Note: all probabilities are obtained by using Excel Function
Now, to work out the solution,
Part (a)
From the given data, mean arrival per 5 minute interval = 108/36 = 3.
So, = 3 ANSWER
Part (b)
Probability of no customer arrival in any 5-minute interval = P(X = 0) = e-3
= 0.0498 ANSWER
Part (c)
Probability of 6 or more customer arrivals in any 5-minute interval = P(X 6)
= 1 – P(X 5) = 1 – 0.9161 = 0.0839 ANSWER
Part (d)
Probability of fewer than 4 customer arrivals in any 10-minute interval = P(X 3/ = 6) [vide (2) under Back-up Theory]
= 0.2851 ANSWER
Part (e)
Probability of no customer arrival in any 10-minute interval = P(X = 0/ = 6) [vide (2) under Back-up Theory]
= 0.0025 ANSWER
Part (f)
Probability of exactly 8 customer arrivals in any 15-minute interval = P(X = 8/ = 9) [vide (2) under Back-up Theory]
= 0.1318 ANSWER