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:
A Transport You Don't Drive
I'm a transport you don't have to drive
Which means you can sit back and relax
I can take you across the country
Not in the air but along some tracks.
What could I be?
Which means you can sit back and relax
I can take you across the country
Not in the air but along some tracks.
What could I be?
Hint:
The Train Of Love
A young man, living in Manhattan, New York, has two girlfriends. One lives to the North, in the Bronx, and the other lives to the South, in Brooklyn.
He likes both girls equally but can only visit one each weekend. He therefore leaves it to chance and takes the first train that arrives when he reaches the train station.
Even though the man arrives at a totally random time every Saturday morning and the Brooklyn and Bronx trains arrive equally often (every ten minutes), he finds himself visiting the girl in Brooklyn on average nine times out of ten. How could the odds so heavily favor taking the Brooklyn train?
He likes both girls equally but can only visit one each weekend. He therefore leaves it to chance and takes the first train that arrives when he reaches the train station.
Even though the man arrives at a totally random time every Saturday morning and the Brooklyn and Bronx trains arrive equally often (every ten minutes), he finds himself visiting the girl in Brooklyn on average nine times out of ten. How could the odds so heavily favor taking the Brooklyn train?
Hint: Think of a way the train schedules might favor one train over the other.
The Brooklyn train leaves exactly 1 minute before the Bronx train.
Let's say the Brooklyn train arrives at 09:00, 09:10, 09:20, etc. and the Bronx train arrives one minute after at 09:01, 09:11, 09:21, etc. Consider the ten minute interval from 09:00 to 09:10. If the man arrives between 09:00 and 09:01, the 09:01 Bronx train will be the first to arrive (assuming that he doesn't arrive at exactly 09:00). If the man arrives between 09:01 and 09:10, the 09:10 Brooklyn train will be the first to arrive. In any ten minute period, the Brooklyn train will be the first to arrive in nine of the ten minutes. Did you answer this riddle correctly?
YES NO
Let's say the Brooklyn train arrives at 09:00, 09:10, 09:20, etc. and the Bronx train arrives one minute after at 09:01, 09:11, 09:21, etc. Consider the ten minute interval from 09:00 to 09:10. If the man arrives between 09:00 and 09:01, the 09:01 Bronx train will be the first to arrive (assuming that he doesn't arrive at exactly 09:00). If the man arrives between 09:01 and 09:10, the 09:10 Brooklyn train will be the first to arrive. In any ten minute period, the Brooklyn train will be the first to arrive in nine of the ten minutes. Did you answer this riddle correctly?
YES NO
I Kept Them Safe Riddle
I kept them safe and showed the way
Once thrown down upon the ground
I came alive with a hissing sound
I hit the rock as he was told
And that was when the water flowed
What am I?
Hint:
Something To Mourn Riddle
I was a gift to the one but poison to the others
I was a favoured sign but also a hated symbol
Some say that of many I was not short
While others talk of two that were far too long
I was stolen and then torn
And became something to mourn
What am i?
I was a favoured sign but also a hated symbol
Some say that of many I was not short
While others talk of two that were far too long
I was stolen and then torn
And became something to mourn
What am i?
Hint: Genesis 37
Out Of Sight Riddle
I can be carried but not touched
I have two on the outside and ten on the inside
Everyone wants to catch a sight of me
But I'm kept out of sight
I was lost and found; then found but now I am lost
I'm in the Bible - what am I?
I have two on the outside and ten on the inside
Everyone wants to catch a sight of me
But I'm kept out of sight
I was lost and found; then found but now I am lost
I'm in the Bible - what am I?
Hint: Exodus 25:10 - 22; 1 Sammuel 4
High In The Sky Riddle
I was high in the sky but also firmly on the earth
I brought cooperation for many but confusion for all
I was unmissable by the crowd yet overlooked by the One
I was the world's first true skyscraper and also its last
I am in the Bible - what am I?
I brought cooperation for many but confusion for all
I was unmissable by the crowd yet overlooked by the One
I was the world's first true skyscraper and also its last
I am in the Bible - what am I?
Hint:
Couples Wait Until Marriage To Share This
Hint:
Fake Ireland Stones Riddle
Hint:
Beginning Of A Journey Riddle
Hint:
Begins With L Riddle
Begins with L and ends with Y
With its presence relationships survive
Through slightest inkling of its loss
Instant separation can be caused.
What is it?
With its presence relationships survive
Through slightest inkling of its loss
Instant separation can be caused.
What is it?
Hint:
A Tested Formula Of Love Riddle
A tested formula of love
Inevitable part of love stories
The romantic dim light and good food are its friends
It never goes out of trend.
What is it?
Inevitable part of love stories
The romantic dim light and good food are its friends
It never goes out of trend.
What is it?
Hint:
Made By God In Pairs Riddle
Separated at birth on Earth
Found after years of search
Inseparable for the rest of the time.
What am I?
Hint:
I Can Be Happy Riddle
I can be happy, sad or confusing. I can show or just be gone, but I'll come back not before long. What am I?
Hint:
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