/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 12 Airlines sometimes overbook flig... [FREE SOLUTION] | 91Ó°ÊÓ

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Airlines sometimes overbook flights. Suppose that for a plane with 50 seats, 55 passengers have tickets. Define the random variable \(Y\) as the number of ticketed passengers who actually show up for the flight. The probability mass function of \(Y\) appears in the accompanying table. \begin{tabular}{l|ccccccccccc} \(y\) & 45 & 46 & 47 & 48 & 49 & 50 & 51 & 52 & 53 & 54 & 55 \\ \hline\(p(y)\) & \(.05\) & \(.10\) & \(.12\) & \(.14\) & \(.25\) & \(.17\) & \(.06\) & \(.05\) & \(.03\) & \(.02\) & \(.01\) \end{tabular} a. What is the probability that the flight will accommodate all ticketed passengers who show up? b. What is the probability that not all ticketed passengers who show up can be accommodated? c. If you are the first person on the standby list (which means you will be the first one to get on the plane if there are any seats available after all ticketed passengers have been accommodated), what is the probability that you will be able to take the flight? What is this probability if you are the third person on the standby list?

Short Answer

Expert verified
a. 0.83; b. 0.17; c. 0.06 for the first, 0.0 for the third standby person.

Step by step solution

01

Define Problem Context

The exercise involves understanding the probability distribution of the random variable \( Y \), which represents the number of ticketed passengers who show up for a flight, on a plane with 50 seats and 55 ticketed passengers. We are asked to determine probabilities related to the seating capacity and standby passengers.
02

Calculate the Probability All Passengers Fit

To find the probability that all ticketed passengers who show up can be accommodated, we need to find \( P(Y \leq 50) \). Sum the probabilities for \( y = 45 \) to \( y = 50 \):\[ P(Y \leq 50) = 0.05 + 0.10 + 0.12 + 0.14 + 0.25 + 0.17 = 0.83 \]
03

Calculate the Probability Some Passengers Overbook

To find the probability that not all ticketed passengers can be accommodated, calculate \( P(Y > 50) \). Sum the probabilities for \( y = 51 \) to \( y = 55 \):\[ P(Y > 50) = 0.06 + 0.05 + 0.03 + 0.02 + 0.01 = 0.17 \]
04

Probability for First Standby List Person

The first standby person can take the flight if more than 50 passengers show up but up to 51 passengers. Calculate the probability \( P(Y = 50) + P(Y = 51) \):\[ P(Y = 51) = 0.06 \] So the standby probability is simply this probability since it will only be possible when exactly 51 people show up after the flight is full.\[ P(Y = 51) = 0.06 \]
05

Probability for Third Standby List Person

To be accommodated, we need exactly 50 passengers to show up for the flight. Therefore, \( P(Y = 50) + P(Y = 51) + P(Y = 52) = 0.17 \) with the additional 2 probabilities for 51 and 52 depending on everyone leaving the flights to even get to third standby.\[ P(Y = 50) \] gives standby 1 with \( P(Y = 51) \) gives standby 2 as \( P(Y = 52) \) which is 0.0 as 52 would mean no left over at 2nd, couldn't do it to make third standby.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Random Variable
In the context of probability, a random variable is a numerical description of the outcome of a random phenomenon. In this exercise, the random variable denoted by \( Y \) represents the number of ticketed passengers who show up for a flight on an airplane. It's crucial to understand that a random variable can take on different values based on the probability distribution assigned to it. Each possible outcome of this random variable is associated with a probability. For example, if 45 passengers show up, this is one possible value of \( Y \), and it has a specified probability according to the given probability mass function.

A probability mass function (PMF) is a function that gives the probability that a discrete random variable is exactly equal to some value. In this case, the PMF is represented by the values given in the problem's table. This function helps us determine the likelihood of any specific number of passengers showing up, ranging from 45 to 55.
  • Having a PMF is essential for making calculations and predictions about random outcomes.
  • In our exercise, it allows us to calculate the probabilities of different scenarios such as all passengers fitting or being able to accommodate standby passengers.

Understanding random variables and their distributions helps in planning and decision-making, especially in scenarios like flight overbooking, where prediction of certain outcomes is vital to optimize resource allocation.
Overbooking
Overbooking is a common practice in the airline industry where airlines sell more tickets than the available seats on a flight. This strategy is used to maximize revenue, based on statistical predictions that not all passengers will show up. In our problem, the airline has overbooked a 50-seat plane by issuing 55 tickets, meaning there are 5 more ticketed passengers than actual seats.

Overbooking relies on understanding probabilities, as it's all about predicting human behavior – the likelihood of passengers showing up versus not showing up.
  • Airlines use historical data to forecast the number of no-shows for any given flight.
  • The goal is to fill every seat while minimizing disruptions caused by too many passengers showing up.

If more passengers show up than there are available seats, some ticketed passengers may not be able to board the flight, creating a need for backup plans, such as offering compensation or arranging alternate flights. Our exercise involves calculating the probability of such overbooking situations, which is useful for airlines in decision-making and customer service management.
Standby Passengers
Standby passengers are individuals who wish to fly on a plane but do not hold a confirmed reservation. They are accommodated on the flight if there are available seats – usually from other passengers not showing up. In this exercise, we're asked to determine the probability that a standby passenger can board, given the number of tickets sold exceeds the seating capacity.

Here's how standby passenger scenarios unfold, based on the defined random variable \( Y \):
  • The first person on the standby list would have the opportunity to board if exactly 51 people show up. The probability of exactly 51 passengers boarding is computed from the PMF, which in this case is 0.06.
  • The likelihood of a standby passenger boarding diminishes with their rank on the standby list. For example, unless fewer passengers show up than anticipated, the third person on the standby list is unlikely to find an available seat.
Calculated probabilities provide insights into the chances of standby passengers getting a seat, helping airports and airlines manage overbooking dynamically. Effective management of standby passengers ensures better customer satisfaction and more efficient resource use.

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