The 100 Seat Airplane
People are waiting in line to board a 100-seat airplane. Steve is the first person in the line. He gets on the plane but suddenly can't remember what his seat number is, so he picks a seat at random. After that, each person who gets on the plane sits in their assigned seat if it's available, otherwise they will choose an open seat at random to sit in.
The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat?
The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat?
Hint: You don't need to use complex math to solve this riddle. Consider these two questions:
What happens if somebody sits in your seat?
What happens if somebody sits in Steve's assigned seat?
The correct answer is 1/2.
The chase that the first person in line takes your seat is equal to the chance that he takes his own seat. If he takes his own seat initially then you have a 100% chance of sitting in your seat, if he takes your seat you have a 0 percent chance. Now after the first person has picked a seat, the second person will enter the plan and, if the first person has sat in his seat, he will pick randomly, and again, the chance that he picks your seat is equal to the chance he picks someone your seat. The motion will continue until someone sits in the first persons seat, at this point the remaining people standing in line which each be able to sit in their own seats. Well how does that probability look in equation form? (2/100) * 50% + (98/100) * ( (2/98) * 50% + (96/98) * ( (2/96) * (50%) +... (2/2) * (50%) ) ) This expansion reduces to 1/2.
An easy way to see this is trying the problem with a 3 or 4 person scenario (pretend its a car). Both scenarios have probabilities of 1/2. Did you answer this riddle correctly?
YES NO
The chase that the first person in line takes your seat is equal to the chance that he takes his own seat. If he takes his own seat initially then you have a 100% chance of sitting in your seat, if he takes your seat you have a 0 percent chance. Now after the first person has picked a seat, the second person will enter the plan and, if the first person has sat in his seat, he will pick randomly, and again, the chance that he picks your seat is equal to the chance he picks someone your seat. The motion will continue until someone sits in the first persons seat, at this point the remaining people standing in line which each be able to sit in their own seats. Well how does that probability look in equation form? (2/100) * 50% + (98/100) * ( (2/98) * 50% + (96/98) * ( (2/96) * (50%) +... (2/2) * (50%) ) ) This expansion reduces to 1/2.
An easy way to see this is trying the problem with a 3 or 4 person scenario (pretend its a car). Both scenarios have probabilities of 1/2. Did you answer this riddle correctly?
YES NO
People Ride On My Back Riddle
I have four legs and a long tail.
I eat oats and hay.
I love to run fast.
I let people ride on my back.
What am I?
I eat oats and hay.
I love to run fast.
I let people ride on my back.
What am I?
Hint:
Servant Of All Great People Riddle
After a few lessons I will do it automatically.
I am the servant of all great people and alas of all failures as well.
What am I?
Hint:
People Might Be British Riddle
This is the name of a continent
Which has fifty different countries
People living there might be British,
French, German, Polish or Maltese
Which has fifty different countries
People living there might be British,
French, German, Polish or Maltese
Hint:
People Cry At My Sight
I have a name that's not mine,
and no one cares about me in their prime.
People cry at my sight,
and lie by me all day and night.
What am I?
and no one cares about me in their prime.
People cry at my sight,
and lie by me all day and night.
What am I?
Hint:
100 Lbs Riddle
Hint:
The Most Talkative People In The Bible
Hint:
I Enter The Garden There Are 34 People Riddle
Hint:
If the backyard and garden are two different locations then there would be one person left in the garden. This is because the murderous rampage took place in the backyard, not the garden. However, the riddle solver considers that the backyard and the garden is the same place then, then zero people would be left, as the killer would technically be counted amongst the 34 people. Did you answer this riddle correctly?
YES NO
YES NO
How Many People?
Hint:
9. Two twins are 2 people, three triplets are 3 people, and four quadruplets are 4 people. 2 + 3 + 4 = 9. Did you answer this riddle correctly?
YES NO
YES NO
This Is What Some People Do Riddle
This is what some people do,
For a compliment or two,
Anglers do it on a bank,
Others keep theirs in a tank.
What am I?
For a compliment or two,
Anglers do it on a bank,
Others keep theirs in a tank.
What am I?
Hint:
Remove My Letters Riddle
I am a five letter word. If you remove all my letters except the first, I sound the same! What am I?
Hint:
Embarrassing People Riddle
Hint:
A Lions Appetite Riddle
Hint:
A Room With Plenty Of Space
Hint:
Satisfies Two People Riddle
Hint:
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