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
The Odds Of A Boy Riddle
Mr. Smith has two children. If the older child is a boy, what are the odds that the other child is also a boy?
Hint:
Turning Water Into Ice Riddle
Hint:
Spell Sexy Riddle
Hint:
Puddle Of Water Riddle
Two cops walked into a room with no windows and found a dead man who obviously hung himself from the ceiling, though they couldn't figure out how. There was no chair beneath him that he might have jumped off of, or a table. Just a puddle of water. How'd he do it?
Hint:
Piping Hot Water Riddle
Late afternoons I often bathe. I'll soak in water piping hot. My essence goes through my see through clothes. Used up am I; I've gone to pot.
I am a?
I am a?
Hint:
Tea Cups On The Table
Hint: Try reading the question out loud.
The answer is 3 tea cups because the question was not forty cups it was four tea cups. Did you answer this riddle correctly?
YES NO
YES NO
A Boy Who Talks To Animals
I lived in London
I wear a yellow dress
I go to Africa to study gorillas
I met a boy who talks to the animals
Who am I?
I wear a yellow dress
I go to Africa to study gorillas
I met a boy who talks to the animals
Who am I?
Hint:
A Boy Born In May Riddle
How could a boy be born in May, although his birthday was in June, and then grow up and marry his mother?
Hint:
He could be born in the month of June in a town called May. When he grows up, he could officiate his mother's wedding and "marry" her to someone else. Did you answer this riddle correctly?
YES NO
YES NO
Soldiers On The River
A detachment of soldiers must cross a river. The bridge is broken, the river is deep. What to do? Suddenly the officer-in-charge spots two boys playing in a rowboat by the shore. The boat is so tiny, however, that it can only hold 2 boys or 1 soldier. Still - all the soldiers succeed in crossing the river in the boat. How?
Hint:
First the boys cross the river. One stays ashore while the other brings the boat to the soldiers. A soldier takes the boat back across and the boy that stayed before brings the boat back and picks up the other boy. The boat takes the two boys back and one remains while the other boy returns the boat to the soldiers. This is repeated until all of the soldiers are on the opposite side of the river. Did you answer this riddle correctly?
YES NO
YES NO
Coffee Diner Riddle
A man walks into a diner and sits down. There's a new waitress working that he's never seen before. When she comes to his table to take his order, he says "Just a cup of coffee please." A few minutes later the waitress brings the man his coffee and heads back to the kitchen. A short while later, the man notices that there is a fly in his coffee and calls the waitress back. He asks her nicely to bring him another cup. The waitress brings the man's cup of coffee back to the kitchen and returns a few moments later. "Here you are, I poured you a new cup of coffee, no fly this time" she says and hands him the cup. The waitress turns around and starts to head back to the kitchen. She only takes a few steps before she hears the man shout out "Hey, this is the same cup of coffee, all you did was remove the fly!"
Assuming the coffee was still hot, how did the man know it was the same cup of coffee?
Assuming the coffee was still hot, how did the man know it was the same cup of coffee?
Hint: A man walks into a diner and sits down. There's a new waitress working that he's never seen before. When she comes to his table to take his order, he says "Just a cup of coffee please." A few minutes later the waitress brings the man his coffee and heads
Because the coffee was sweet. The man had added sugar to his coffee before noticing the fly. When the waitress brought him the "new" cup of coffee, he took a sip (to check whether it was in fact a newly poured cup of coffee) and noticed that the coffee was "already" sweet. Did you answer this riddle correctly?
YES NO
YES NO
Water And Light Riddle
Hint:
The Land Surrounded By Water
You might get to one by airplane
Or you might prefer to go by boat
As its surrounded by water
But its not a castle with a moat
Or you might prefer to go by boat
As its surrounded by water
But its not a castle with a moat
Hint:
Th One Called Coney Riddle
There is one called Madagascar
But it isnt a movie
And if you want a good hot dog
Go to the one called Coney.
Where could this be?
But it isnt a movie
And if you want a good hot dog
Go to the one called Coney.
Where could this be?
Hint:
Five Weeks Old Riddle
Born at the same time as the world, destined to live as long as the world, and yet never five weeks old. What is it?
Hint:
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