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
Buying A Tortoise Riddle
Hint:
Pig And A Tortoise Riddle
Hint:
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source: http://www.jokes4us.com/animaljokes/turtlejokes.html Did you answer this riddle correctly?
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source: http://www.jokes4us.com/animaljokes/turtlejokes.html Did you answer this riddle correctly?
YES NO
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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:
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My daughter has many sisters. She has as many sisters as she has brothers. Each of her brothers has twice as many sisters as brothers. How many sons and daughters do I have?
Hint:
Four daughters and three sons. Each daughter has 3 sisters and 3 brothers, and each brother has 2 brothers and 4 sisters. Did you answer this riddle correctly?
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Hint:
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One night a father and his son went camping.The next day they returned. Who went camping and who stayed home?
Hint:
Night is actually a homophone for knight so the knight stayed home and the father and son went camping! Did you answer this riddle correctly?
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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?
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Hint:
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A man walks into an art museum and stares at a painting.When a guard walks up and ask him why he is so interested in the painting he responds with "brothers and sisters I have none but that man's father is my father's son" who is the man in the painting?
Hint:
Two Fathers Two Sons Riddle
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Two Fathers And Two Sons
Two fathers and two sons go fishing together in the same boat. They all catch a fish but the total catch for the day is three fish. How is this possible?
Hint:
There are three men: A grandfather, a father (the grandfathers son) and the fathers son. Did you answer this riddle correctly?
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YES NO
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