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
Fifty One Bicycles
Hint:
The man was playing a poker game and cheated. The bicycles are a type of card. Did you answer this riddle correctly?
YES NO
YES NO
Footprints Between Two Parallel Lines Riddle
A man was found dead out in a field of snow. The only tracks that were left was a set of footprints between two parallel lines. Who should the police be looking for?
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
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
Who Was Lying Riddle
There is a man found dead in a circular mansion. The detective interviews the cook, maid, and babysitter. The cook said he couldn't have done it because he was preparing the meal. The maid said she couldn't have done it because she was dusting the corners. The babysitter said she couldn't because she was playing with the children. Who was lying?
Hint:
The Police Know Riddle
Shauna was killed one Sunday morning. The police know who they are going to arrest from this bit of information:
April was getting the mail
Alyssa was doing laundry
Reggie was cooking
Mark was planting in the garden
Who killed Shauna and how did the police know who to arrest?
April was getting the mail
Alyssa was doing laundry
Reggie was cooking
Mark was planting in the garden
Who killed Shauna and how did the police know who to arrest?
Hint:
April killed Shauna because there is no mail delivery on Sundays. Did you answer this riddle correctly?
YES NO
YES NO
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:
Weight From A Barrel Riddle
Hint:
No Way In Or Out Riddle
It is a stormy, snowy day. There is a man dead inside a shack. There are no windows and the only door is locked from inside. There is no way in or out. The man has a stab wound. There is a puddle of water and blood next to him. How did he die?
Hint:
A Man In The Shadows Riddle
You are walking down a dark alley at night. Suddenly, a man jumps out of the shadows with a gun. He tells you "I am here to kill you. Tell me one wish. I will not fulfill it, but I will kill you. If you say the right thing, you will be saved." What do you say?
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
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
Killed Her Own Sister Riddle
A woman killed her own sister. During the interrogation, she told a story that she had just attended her own mother's funeral a few days before the crime took place. While at the funeral, she said that she met a guy whom she did not know. She thought this guy was amazing, so much her dream guy that she believed him to be just that! She fell in love with him right there, but never asked for his number and could not find him. A few days later, she killed her sister.
Although this woman has confessed to the crime, police are still intrigued by the story, especially because she won't tell them her motive. Hearing this tragic story, with his psychological education background, Detective Thompson easily guessed the woman's motive.
Why did the woman killed her own sister?
Although this woman has confessed to the crime, police are still intrigued by the story, especially because she won't tell them her motive. Hearing this tragic story, with his psychological education background, Detective Thompson easily guessed the woman's motive.
Why did the woman killed her own sister?
Hint:
She was hoping that the guy would appear at the funeral again. Did you answer this riddle correctly?
YES NO
YES NO
Deadly Punch Riddle
A man went into a party and drank some of the punch. He then left early. Everyone at the party who drunk the punch subsequently died of poisoning. Why did the man not die?
Hint:
The poison from the punch came from the ice cubes. When the man drank the punch, the ice was fully frozen. Gradually, as the ice cubes melted the poison was released into the punch. Did you answer this riddle correctly?
YES NO
YES NO
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