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
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
Running Through Fields And Woods Riddle
Riddle me this
I run over fields and woods all day. Under the bed at night I sit, never alone. My tongue hangs out, up and to the rear, waiting to be filled in the morning. What am I?
I run over fields and woods all day. Under the bed at night I sit, never alone. My tongue hangs out, up and to the rear, waiting to be filled in the morning. What am I?
Hint:
Five Apples Riddle
There were five women sitting in a room. In the same room there was a basket with five apples in it. Each woman took an apple, but one apple still remained in the basket. How could this be?
Hint:
The fifth woman took the entire basket, with the apple still in it. Did you answer this riddle correctly?
YES NO
YES NO
I Am Up In The Sky
I am white, I hang out being where birds take flight. I am up n the sky so I can sit and spy, I look down on every fellow. When I'm gone you seek your pillow. What am I?
Hint:
The Red Hat
Once upon a time there lived a king who wished to find the wisest man in the realm to be his assistant. He summons the 3 known wisest men to his court and he administers the following test.
He sits them in a circle, facing each other and he says Im going to put either a red hat or a white hat on each of your heads. He proceeds to place a red hat on each of their heads. Obviously they can see each other but there are no mirrors in the room so they cant see whats on their heads. He says If you can see a red hat, raise your hand. They all raise their hands. Then he says If you can tell what color hat you have on, stand up.
Time goes on, one guy looks at another guy, he looks at the other guy. The other guy looks at him. Finally one guy stands up. The question is how did he know he was wearing a red hat?
He sits them in a circle, facing each other and he says Im going to put either a red hat or a white hat on each of your heads. He proceeds to place a red hat on each of their heads. Obviously they can see each other but there are no mirrors in the room so they cant see whats on their heads. He says If you can see a red hat, raise your hand. They all raise their hands. Then he says If you can tell what color hat you have on, stand up.
Time goes on, one guy looks at another guy, he looks at the other guy. The other guy looks at him. Finally one guy stands up. The question is how did he know he was wearing a red hat?
Hint: For a moment or two, nobody moved. Nobody knew for certain what color his hat was, and thats what told the wisest guy that all of the hats were red.
Step 1:
Wiseguy #1 knows he can see two red hats.
Step 2:
Wiseguy #1 thinks, "Hey, if I were wearing a white hat, Wiseguy #2 would see one red hat and one white."
Step 3:
Wiseguy #1 then thinks, "If I were wearing a white hat, and Wiseguy #2 saw one red hat and one white (and if he were wearing a white hat himself), then Wiseguy #3 would have seen two white hats. So, Wiseguy #3 wouldnt have raised his hand to the first question.
Wiseguy #1 thinks, "If that were true, Wiseguy #2 would be sure that he had a red hat. But since Wiseguy #2 was actually unsure about his hat color, it can only mean one thing, my hat is red." Did you answer this riddle correctly?
YES NO
Wiseguy #1 knows he can see two red hats.
Step 2:
Wiseguy #1 thinks, "Hey, if I were wearing a white hat, Wiseguy #2 would see one red hat and one white."
Step 3:
Wiseguy #1 then thinks, "If I were wearing a white hat, and Wiseguy #2 saw one red hat and one white (and if he were wearing a white hat himself), then Wiseguy #3 would have seen two white hats. So, Wiseguy #3 wouldnt have raised his hand to the first question.
Wiseguy #1 thinks, "If that were true, Wiseguy #2 would be sure that he had a red hat. But since Wiseguy #2 was actually unsure about his hat color, it can only mean one thing, my hat is red." Did you answer this riddle correctly?
YES NO
Reading In The Dark
It was pitch black one evening. A girl was sitting on the balcony at 8 pm. There was no power in the house and the entire street was dark.She was reading a book. How?
Hint:
Making Faces Riddle
When asked what he does all day, a man answered that he sits and makes faces. What does he really mean?
Hint:
Swishing To The Ground
Hint:
I'm A Yellow Fellow Riddle
Im a yellow fellow with a pointed head.
As thin as thin can be.
But I leave a trail on a blank white page
When someone writes with me. What might I be?
As thin as thin can be.
But I leave a trail on a blank white page
When someone writes with me. What might I be?
Hint:
On Top A Joppa House Riddle
There was a man who went one day
On top a Joppa house to pray,
And while he waited for his meat
He dreamed he saw a great big sheet
Let down from heaven, and inside
Fowls and creeping things did ride,
The one who prayed was told to eat,
For God had cleansed this "common" meat.
Who was he?
On top a Joppa house to pray,
And while he waited for his meat
He dreamed he saw a great big sheet
Let down from heaven, and inside
Fowls and creeping things did ride,
The one who prayed was told to eat,
For God had cleansed this "common" meat.
Who was he?
Hint:
Two Thousand Pound Gorilla Riddle
Hint:
I'm A Dividing Line At An Edge
I'm a dividing line at an edge; a squiggle of land lacking rock or ledge. I stretch out far and sometimes wide, but you'll stay dry if you pick my side. There's salt on my breath, and I've sand for feet; you sometimes sit with me in the heat. When waves come to call, I hold them back- keeping your visit right on track. But remember, should they ever choose to rise, those who leave surly are wise.
What am I?
What am I?
Hint:
Fear Of The Ocean
Three men sitting in a small motorboat one mile from the shoreline. The first is afraid of water, the second afraid of drowning, and the third afraid of sharks. The boats motor is not operational and there is nothing to row with. How do they get to the shoreline?
Hint:
Albatross Boat Riddle
Two men walk into a restaurant by the sea and sit at the bar. Both men are covered in water. Both men order a plate of Albatross and take one bite. After chewing and swallowing, the first man stands up, walks outside, and shoots himself, while the other finishes his meal.
Hint:
The two men were stranded out in the ocean with a third man when they were beginning to stave. When an albatross landed on their life boat and died they finally had food but it was not enough to feed all three of them. They drew straws and the looser was killed and eaten. They mixed up the human meat and the albatross meat so neither person would know what they were eating. After being rescued, the friends went to eat real Albatross and the man who killed himself realized that he was the one that ate his friend. Did you answer this riddle correctly?
YES NO
YES NO
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