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:
The Sturdy Feet Of Man
I cannot stand on my two feet;
I need help from one who can.
But in motion, they're superior
To the sturdy feet of man.
What am I?
I need help from one who can.
But in motion, they're superior
To the sturdy feet of man.
What am I?
Hint:
Add Up To 100 Riddle
With the numbers 123456789, make them add up to 100. They must stay in the same order. You can use addition, subtraction, multiplication, and division. Remember, they have to stay in the same order!
Hint:
Feet On A Farm Riddle
Hint:
Just four. His wife has two feet, he has two feet, each chicken has two claws, each horse has four hoofs. Did you answer this riddle correctly?
YES NO
YES NO
Two Girls Born The Same Day Riddle
Hint:
Women With The Smallest Feet
Hint:
It's one of those "evolutionary things" that allows them to stand closer to the kitchen sink. Did you answer this riddle correctly?
YES NO
YES NO
I Lie At Your Feet Riddle
Each morning I appear to lie at your feet. All day I will follow no matter how fast you run. Yet I nearly perish in the midday sun. What am I?
Hint:
Rubbing Your Feet Riddle
I don't go out and play, I just stay home all day, I'm nice - you might agree, but mostly your feet just rub me?
Hint:
Laying The World At Your Feet
Those who are great I have made great,
Those who are failures I have made failures.
I am not a machine, but I work with all of the precision of a machine,
Plus the intelligence of a person.
Now, you may run me for profit or you may run me
For ruin. It makes no difference to me.
Take me, train me, be firm with me,
And I will lay the world at your feet.
Be easy with me and I will destroy you.
Who am I?
Those who are failures I have made failures.
I am not a machine, but I work with all of the precision of a machine,
Plus the intelligence of a person.
Now, you may run me for profit or you may run me
For ruin. It makes no difference to me.
Take me, train me, be firm with me,
And I will lay the world at your feet.
Be easy with me and I will destroy you.
Who am I?
Hint:
Smoking Girlfriend Riddle
Hint:
Backwards And Upside Down Riddle
Hint:
100 Widgets Riddle
Hint:
It would take 5 minutes. Each machine takes 5 minutes to make its widget. Therefore, each of the 100 machines would have finished making its widget in 5 minutes. Did you answer this riddle correctly?
YES NO
YES NO
Never Coming Back Riddle
I'm sometimes white and sometimes black.
I'll take you there, but never bring you back.
What could I be? Body parts remaining: 6
I'll take you there, but never bring you back.
What could I be? Body parts remaining: 6
Hint:
The Girl Squirrel Riddle
Hint:
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