# Aeroplane Problem

What is the probability that you will again meet a person on a plane (flying one)?

Details and Assumption

• There is only one plane company
• You cannot Hack into the company server nor you can get any information about the person
• You have the worst luck and still there is a chance you will meet him/her.
• Every person only travels on plane.
• Nor u can take his/her number or ask him/her which flight they have taken.
• You only know that when the person is travelling and it corresponds to your date.
• No. of planes per day is between 1000 to 10000000.
• No. of persons in a plane is 8000 (always)
• No. of persons in the country $10^{10}$.
• Flight cannot get cancelled
• No one misses the flight.

Actually I met my old friend on a plane recently, So I came up with this problem

Note by Department 8
5 years, 3 months ago

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You cannot determine the probability.What if you meet a person on a plane and that person never flies on a plane again?

- 5 years, 3 months ago

I have edited it please review.

- 5 years, 3 months ago

Still you need to know how many planes leave per day and how many people can be there is a plane.

- 5 years, 3 months ago

Check it now.

- 5 years, 3 months ago

How many people are there in that city/country? How often does a person travel?

- 5 years, 3 months ago

Review

- 5 years, 3 months ago

Do you orient your time to specifically give you best chance of meeting him? Does he have a systematic routine? Can he miss his flight, if so will he take the next flight? Can you miss your flight, if so can you take the next flight?

- 5 years, 3 months ago

Do all the people in the city use the plane? How frequently do they use the plane? Can they miss their flights , if so are their seats given to someone else? Are the seats filled stack-wise or can a random person take a random plane?

- 5 years, 3 months ago

What if two people book the same seat at the same time? Can there be technical difficulties while booking? If he doesn't get his preferred flight timing will he take tomorrow's flight or an inconvenient flight?

- 5 years, 3 months ago

Well, you get the point

- 5 years, 3 months ago

There has to be an exact number of flights that have to leave per day to possibly determine the probability.

- 5 years, 3 months ago

Approx the probability or range them

- 5 years, 3 months ago

You should also mention that a flight cannot get cancelled and each flight carries 8000 people always.

- 5 years, 3 months ago

I don't get it. How many flights are there supposed to be per day? Will he certainly take a flight? Will you certainly take a flight? If so, is it on the same day? How many people are there on the plane? (If that is relevant, expecting fully booked planes to stack to next plane). Do you know his flight time? Too many factors.

- 5 years, 3 months ago

- 5 years, 3 months ago

@Lakshya Sinha There are tons of affecting the probability. Even if you are able to list all the factors, the probability will be very very small.

- 5 years, 3 months ago

Wow, the probability is very low. It is not easy to calculate. Although I am in my profession (I am conducting due diligence), I do a lot of calculations, read about it <a target="_blank" rel="nofollow" href="http://en.clc.co.ua/due-diligence-ukraine/">click here</a>. I certainly will not calculate the probability, but I calculate the risks for business buyers.

- 2 years, 3 months ago