An airline estimates that 92% of people booked on their flights actually show up. If the airline books 75 people on a flight for which the maximum number is 73, what is the probability that the number of people who show up will exceed the capacity of the plane?

Respuesta :

Answer:

The probability is 0.0144

Step-by-step explanation:

The probability that x people show up follows a binomial distribution, so it is equal to:

[tex]P(x)=\frac{n!}{x!(n-x)!}*p^{x}*(1-p)^{n-x}[/tex]

Where n is the number of booked people and p is the probability that a person shows up. Then, the probability that x people show up is:

[tex]P(x)=\frac{75!}{x!(75-x)!}*0.92^{x}*(1-0.92)^{75-x}[/tex]

So, the probability that the number of people who show up will exceed the capacity of the plane is:

P(x>73) = P(74) + P(75)

Where P(74) and P(75) are calculated as:

[tex]P(74)=\frac{75!}{74!(75-74)!}*0.92^{74}*(1-0.92)^{75-74}=0.0125[/tex]

[tex]P(75)=\frac{75!}{75!(75-75)!}*0.92^{75}*(1-0.92)^{75-75}=0.0019[/tex]

Finally, P(x>73) is:

P(x>73) = 0.0125 + 0.0019 = 0.0144