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
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
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:
Found Near A Leprechaun
Im curved but Im not a banana
Im mentioned in the first book of the Bible but Im not a snake
Im colorful but Im not a parrot
Im mentioned in a Wizard Of Oz song but Im not a Yellow Brick Road
Im found near a leprechaun but Im not a pot of gold.
What am I?
Im mentioned in the first book of the Bible but Im not a snake
Im colorful but Im not a parrot
Im mentioned in a Wizard Of Oz song but Im not a Yellow Brick Road
Im found near a leprechaun but Im not a pot of gold.
What am I?
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:
Rings Tell My Age Riddle
Hint:
Rings Of Age Riddle
People climb me, cut me and burn me, they show me no respect! My rings are not of gold, but they do tell my age?
Hint:
Vampire Savings Riddle
Hint:
Presidential Promises Riddle
Ronald has a rare opportunity to meet the President of the United States. During his visit the president gives him a gift but tells Ronald he is never to sell it unless he sees the president again. Ronald consents, but the president dies later that year. Years later a man offers to buy the Presidents gift for $1000. Ronald agrees and exchanges the gift for 20 crisp $50 bills. Did he keep his promise?
Hint:
Yes. The president was Ulysses S. Grant, who died in 1885 and whose face has been on the $50 bill since 1913. He saw the president on the bills before he made the exchange. Did you answer this riddle correctly?
YES NO
YES NO
A Dime And A Dollar Riddle
Hint:
Boxes Of Balls Riddle
The first box has two white balls. The second box has two black balls. The third box has a white and a black ball.
Boxes are labeled but all labels are wrong!
You are allowed to open one box, pick one ball at random, see its color and put it back into the box, without seeing the color of the other ball.
How many such operations are necessary to correctly label the boxes?
Boxes are labeled but all labels are wrong!
You are allowed to open one box, pick one ball at random, see its color and put it back into the box, without seeing the color of the other ball.
How many such operations are necessary to correctly label the boxes?
Hint:
Just One!
Because we know all labels are wrong.
So the BW box must be either BB or WW. Selecting one ball from BW will let you know which.
And the other two boxes can then be worked out logically. Did you answer this riddle correctly?
YES NO
Because we know all labels are wrong.
So the BW box must be either BB or WW. Selecting one ball from BW will let you know which.
And the other two boxes can then be worked out logically. Did you answer this riddle correctly?
YES NO
Joseph And Lena Riddle
Joseph and Lena are found dead on the floor with some water around. The windows are open and a strong wind draft is blowing the curtains around. How did they die?
Hint:
Joseph and Lena were goldfishes. The wind tipped their bowl over, hence killing them! Did you answer this riddle correctly?
YES NO
YES NO
5 Houses Riddle
Here's more information:
An Englishman resides in a red house.
The Dane drinks tea.
Dogs are kept by the Swede.
The green house is left to the white house.
The occupant of the green house drinks coffee.
The birds are kept by the Pall Mall smoker.
The horse keeper and the Dunhill smoker live next to each other.
The German smokes Prince.
The Norwegian lives right next to the blue house.
The blend smoker's neighbor drinks water.
Hint:
The Riddle Of Gestumblindi Scandinavia
Four hang, four sprang, two point the way, two to ward off dogs, one dangles after, always rather dirty. What am I?
Hint:
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