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
Discharge Of The Rifle
Anderson, Biggs, and Carpenter were staying together at a place by the seaside. One day they went out in a boat and were a mile at sea when a rifle was fired on shore in their direction.
It seems that Anderson only heard the report of the gun, Biggs only saw the smoke, and Carpenter merely saw the bullet strike the water near them. Which of them first knew of the discharge of the rifle?
It seems that Anderson only heard the report of the gun, Biggs only saw the smoke, and Carpenter merely saw the bullet strike the water near them. Which of them first knew of the discharge of the rifle?
Hint:
Biggs, who saw the smoke, would be first; Carpenter, who saw the bullet strike the water, would be second; and Anderson, who heard the report, would be last of all. Did you answer this riddle correctly?
YES NO
YES NO
Today's Bar Special Riddle
A man walks into a bar and says: Give me today's special. The bartender says: In a shot or a bottle? The man says: In a shot. The bartender gives it to him. He drinks it and then he dies. Why did he die?
Hint:
The Long Island Iced Tea
Two guys walk into a bar. They both order the special, Long Island Iced Tea, which is poured from the same pitcher. One of them drinks his drink slowly and one of them drinks it fast. They walk outside and suddenly the guy who drank his Long Island Tea slowly drops to the ground and dies. They order an autospy and find that he died from poison. How could this be if the other guy drank the same tea and didnt even get sick?
Hint:
TTwo guys walk into a bar. They both order the special, Long Island Iced Tea, which is poured from the same pitcher. One of them drinks his drink slowly and one of them drinks it fast. They walk outside and suddenly the guy who drank his Long Island Tea slowly drops to the ground and dies. They order an autospy and find that he died from poison. How could this be if the other guy drank the same tea and didnt even get sick? Did you answer this riddle correctly?
YES NO
YES NO
Almost Hit By A Car Riddle
A man walked home after having been out drinking. He walked down the middle of a deserted country road. There were no streetlights to illuminate the road and there was no moonlight. He was dressed all in black. Suddenly a car that did not have its headlights on came racing down the road. At the last moment, the driver of the car saw the man and swerved to avoid him.
How did he manage to see him?
How did he manage to see him?
Hint:
He was returning home in the middle of the day, so anyone could have seen him. Did you answer this riddle correctly?
YES NO
YES NO
A Book In A Bar Riddle
Hint:
Crossing The River Safely Riddle
A man is traveling with a fox and two chickens. If he leaves the fox alone with the chickens, the fox will eat the chickens. He comes to a river and needs to cross it. He finds a small boat that can carry only him and one animal. How does he get himself, the fox and two chickens across the river safely?
Hint:
Take the fox over, return with nothing. Go over with one chicken, return with the fox. Go over with the second chicken, return with nothing. Finally, take the fox over. Did you answer this riddle correctly?
YES NO
YES NO
20 Apples Riddle
There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?
Hint:
Poor Mr. Teddy
Poor Mr. Teddy was found dead in his study by Mr. Fiend.
Mr. Fiend recounted his dismal discovery to the police:
I was walking by Mr. Teddys house when I thought I would just pop in for a visit. I noticed his study light was on and I decided to peek in from the outside to see if he was in there. I walked through the snow towards the window, and I had to wipe the condensation off the window to see inside. That is when I saw his body. I kicked in the front door to confirm my suspicions of foul play. I called the police immediately afterward.
The officer immediately arrested Mr. Fiend for the murder of Mr. Teddy.
How did he know Mr. Fiend was lying?
Mr. Fiend recounted his dismal discovery to the police:
I was walking by Mr. Teddys house when I thought I would just pop in for a visit. I noticed his study light was on and I decided to peek in from the outside to see if he was in there. I walked through the snow towards the window, and I had to wipe the condensation off the window to see inside. That is when I saw his body. I kicked in the front door to confirm my suspicions of foul play. I called the police immediately afterward.
The officer immediately arrested Mr. Fiend for the murder of Mr. Teddy.
How did he know Mr. Fiend was lying?
Hint:
Condensation forms on the inside of the window in the winter, not on the outside. So Mr. Fiend could not have wiped it off to discover Mr. Teddys body. Did you answer this riddle correctly?
YES NO
YES NO
It Was Murder Riddle
A body is found at the bottom of a multistory building. Seeing the position of the body it is evident that the person jumped from one of the windows.
A homicide detective is called to look after the case. He goes to the first floor and walks in the room facing the direction in which the body was found. He opens the window in that direction and flips a coin towards the floor.
Then he goes to the second floor and repeats the process. He keeps on doing it till the last floor. Then, when he climbs down, he tells the team that it is a murder not suicide.
How did he come to know that it was a murder?
A homicide detective is called to look after the case. He goes to the first floor and walks in the room facing the direction in which the body was found. He opens the window in that direction and flips a coin towards the floor.
Then he goes to the second floor and repeats the process. He keeps on doing it till the last floor. Then, when he climbs down, he tells the team that it is a murder not suicide.
How did he come to know that it was a murder?
Hint:
At each floor, he did the same task of opening the window and flipping the coin. If it was a suicide, then at least the window at any of the floors must have been left open by the person who jumped off. The situation only suggests that someone pushed him off and then closed the window again. Did you answer this riddle correctly?
YES NO
YES NO
Puddle Of Water Riddle
Hint:
The Smuggler Riddle
Every day, a man crosses the border of Mexico on a bicycle with two bags of sand. The customs officers check his bags and they are full of sand. The custom officers are aware that he is smuggling something but are not sure what is it exactly. As they do not have any evidence, they let him cross the border. What is he smuggling?
Hint:
A Bed That Never Sleeps
Hint:
Murdered On A Sunday Afternoon
Maid: I was fixing the table.
Cook: I was cooking breakfast.
Butler: I was polishing the silverware and the dishes.
Gardener: I was planting tomato seeds.
Wife: I was reading a book.
Who did it?
Hint:
The cook did it. You don't cook breakfast in the afternoon. Did you answer this riddle correctly?
YES NO
YES NO
Taller Than Any Tree Riddle
Hint:
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