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
Rouge Pilot In Germany
A rogue pilot was about to bomb Germany! The command was given, the hatch was opened and the bomb was released.
Why didn't it ever hit the ground?
Why didn't it ever hit the ground?
Hint:
The Uncharted Island Riddle
A plane containing 5 people crashes into an uncharted island, and all of them survive for a limit of 5 days. 2 of them build themselves graves and die in it from the hard work. 1 person fills one of the graves with dirt and then dies next to it on day 3. The last two people build 3 graves, and put in one of the corpses, but 5 years later, 11 people are not in their graves, yet the graves are full of corpses. How?
Hint:
On day four, the last two survivours(who are different sexes)found food which will last each of them 4 more years, and on the fifth day, they began reproducing. By the fourth year, ten children have been taught how to raise themselves. The children were thoughtful and put their corpses in the grave. Did you answer this riddle correctly?
YES NO
YES NO
Every Single Person Riddle
Hint:
The married people are still alive because every SINGLE person dies. Did you answer this riddle correctly?
YES NO
YES NO
It Lives In Africa Riddle
It lives in Africa
From tall trees it does peck
This creatures most well known
For having a long neck
What is it?
From tall trees it does peck
This creatures most well known
For having a long neck
What is it?
Hint:
Precious Metal Riddle
Some people bite into it
But it is not a carrot
It is a precious metal
Thats pure 24 karat
What is it?
But it is not a carrot
It is a precious metal
Thats pure 24 karat
What is it?
Hint:
Not Gold Or Cooper Riddle
It is a type of metal
Thats sometimes used for a necklace
Its not gold or copper though
Ag is the symbol for this
What is it?
Thats sometimes used for a necklace
Its not gold or copper though
Ag is the symbol for this
What is it?
Hint:
Before A Movie Man Riddle
This can be used to flatten clothes
Or in golf to hit a ball
This goes before a movie Man
And is a type of metal
What is it?
Or in golf to hit a ball
This goes before a movie Man
And is a type of metal
What is it?
Hint:
Common Metal Riddle
This is a common type of metal
With the chemical symbol Fe
When mixed with oxygen and water
You will find that it can get rusty
What is it?
With the chemical symbol Fe
When mixed with oxygen and water
You will find that it can get rusty
What is it?
Hint:
I Bake, I Rest Riddle
I bake, I rest, I come in different shapes, sizes, and types. I am eaten, I am sliced, I am licked, poked, squashed, and I have a man and woman on my head. What am I?
Hint:
Grand Central Station Riddle
This is a type of transport
You can take all over the nation
You travel on railroads
And might stop at Grand Central Station.
What am I?
You can take all over the nation
You travel on railroads
And might stop at Grand Central Station.
What am I?
Hint:
A Locomotive Pull Riddle
This is a way you can get around
It has a locomotive pull it
Its wheels go on top of rails
Japan has a type called the Bullet.
What is it?
It has a locomotive pull it
Its wheels go on top of rails
Japan has a type called the Bullet.
What is it?
Hint:
Two Trains Riddle
Two incredibly high speed trains are charging at a speed of 250 mph, on the same track, starting from opposite directions. They leave at the same exact time and continue at the same exact speed. They never slow down. The two trains never touch...how is that possible?
Hint:
The two trains begin back-to-back and charge the track away from each other. Did you answer this riddle correctly?
YES NO
YES NO
Here Comes The Bride Riddle
I frolic down the aisle to announce here comes the bride. And on my merry way I drop petals by my side. Who am I?
Hint:
Two Girls On A Train
Two schoolgirls were traveling from the city to a dacha (summer cottage) on an electric train.
"I notice," one of the girls said "that the dacha trains coming in the opposite direction passes us every 5 minutes. What do you think-how many dacha trains arrive in the city in an hour, given equal speeds in both directions?"
"Twelve, of course," the other girl answered, "because 60 divided by 5 equals 12."
The first girl did not agree. What do you think?
"I notice," one of the girls said "that the dacha trains coming in the opposite direction passes us every 5 minutes. What do you think-how many dacha trains arrive in the city in an hour, given equal speeds in both directions?"
"Twelve, of course," the other girl answered, "because 60 divided by 5 equals 12."
The first girl did not agree. What do you think?
Hint:
If the girls had been on a standing train, the first girl's calculations would have been correct, but their train was moving. It took 5 minutes to meet a second train, but then it took the second train 5 more minutes to reach where the girls met the first train. So the time between trains is 10 minutes, not 5, and only 6 trains per hour arrive in the city. Did you answer this riddle correctly?
YES NO
YES NO
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