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
A Shy Guy Riddle
Hint:
Who Stole The Money Riddle
A man placed a $100 dollar bill on his desk and left for work. When he returned back the money was gone. He has three suspects: the cook, the maid and the electrician.
The cook said he put the bill under a book on his desk to keep it safe. The man checked and it is no longer there.
The maid said she moved the bill to the inside of the book between page 1 and 2 while she was cleaning. Again, the man checked the book and there was nothing between page 1 and 2.
The electrician said he saw the bill sticking out of the book and he moved it between page 2 and 3 to keep it safe.
Who stole the money?
The cook said he put the bill under a book on his desk to keep it safe. The man checked and it is no longer there.
The maid said she moved the bill to the inside of the book between page 1 and 2 while she was cleaning. Again, the man checked the book and there was nothing between page 1 and 2.
The electrician said he saw the bill sticking out of the book and he moved it between page 2 and 3 to keep it safe.
Who stole the money?
Hint:
The electrician stole the money.
If the man checked for the money between page 1 and 2 of the book, then page 2 and 3 will be opposite sides of a single page and will not be able to hold the money.
Did you answer this riddle correctly?
YES NO
If the man checked for the money between page 1 and 2 of the book, then page 2 and 3 will be opposite sides of a single page and will not be able to hold the money.
Did you answer this riddle correctly?
YES NO
3 Or 4 Prongs Riddle
These riddles all rhyme
Theyre just like some songs
The next thing to find
Has three or four prongs.
Theyre just like some songs
The next thing to find
Has three or four prongs.
Hint:
Goes But Never Grows Riddle
Hint:
Taller Than Any Tree Riddle
Hint:
Breakfast And Tea Riddle
People can sell me, yet I have many clones.
I can bring you laughter between breakfast and tea,
Yet I can also break your heart easily.
I cover the earth like trees of old,
Whose leaves can blind and yet enfold.
Hint:
A book. Authors can speak to you through a book, yet the book makes no sound. Books are sold and have many duplicate copies. A book can bring the reader to tears and laughter, they span the globe and the leaves of a book (a single sheet in a book is called a leaf) can get you wrapped up in the story that youre unaware of whats going on around you. Did you answer this riddle correctly?
YES NO
YES NO
Flip The Switch Riddle
There is a prison with 100 prisoners, each in separate cells with no form of contact. There is an area in the prison with a single light bulb in it. Each day, the warden picks one of the prisoners at random, even if they have been picked before, and takes them out to the lobby. The prisoner will have the choice to flip the switch if they want. The light bulb starts off.
When a prisoner is taken into the area with the light bulb, he can also say "Every prisoner has been brought to the light bulb." If this is true all prisoners will go free. However, if a prisoner chooses to say this and it's wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.
Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.
What strategy could they use to ensure they will go free?
When a prisoner is taken into the area with the light bulb, he can also say "Every prisoner has been brought to the light bulb." If this is true all prisoners will go free. However, if a prisoner chooses to say this and it's wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.
Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.
What strategy could they use to ensure they will go free?
Hint:
Only allow one prisoner to turn the light bulb off and all of the others turn it on if they have never turned it on before. If they have turned it on before they do nothing. The prisoner that can turn it off then knows they have all been there and saves them all when he has turned it off 99 times. Did you answer this riddle correctly?
YES NO
YES NO
I Can Speak Any Language Riddle
My stem's planted firmly where I am allotted.
My tail is wavy and my face is quite blotted.
I relay much emotion though flatly I'm spotted,
And I grow half my size whenever I'm dotted.
I can speak any language, yet utter no words.
I'm no seed, yet I am well known among birds.
But I do have a speech impediment:
I can say cage but not page, aged but not wage.
I can say deaf but not red, bed but not sled.
I live on a highway that's structurally sound,
Where you might see my friends accidentally bound.
It has many lanes, and also long lines.
There are lots of sharp turns, but plenty of signs.
I am played but not won, made but not spun.
The key is to measure before you've begun.
What am I?
My tail is wavy and my face is quite blotted.
I relay much emotion though flatly I'm spotted,
And I grow half my size whenever I'm dotted.
I can speak any language, yet utter no words.
I'm no seed, yet I am well known among birds.
But I do have a speech impediment:
I can say cage but not page, aged but not wage.
I can say deaf but not red, bed but not sled.
I live on a highway that's structurally sound,
Where you might see my friends accidentally bound.
It has many lanes, and also long lines.
There are lots of sharp turns, but plenty of signs.
I am played but not won, made but not spun.
The key is to measure before you've begun.
What am I?
Hint:
Pounds Of Sugar Riddle
The grocer had ten customers, each wanting to buy a 2 pound bag of sugar. A 20 pound bag of sugar had been delivered that morning, but he had not yet divided it because he could only find the 5lb and 9lb weights. One of the customers, getting impatient, showed him the quickest way to measure the sugar with the two weights he already had. How did he do it?
Hint:
Weigh out 4 pounds of sugar with the 5lb and the 9lb weights in different pans of the scales. With the 4lb weight , weigh three more lots of 4 pounds each - the remaining sugar will also weigh 4 pounds. Divide each 4 pound portion equally on the two sides of the scales. Did you answer this riddle correctly?
YES NO
YES NO
The Color Of Leaves On The Trees
A nice, crisp dollar bill
And the leaves up on the trees
A tasty cucumber
Whats the color of all these?
And the leaves up on the trees
A tasty cucumber
Whats the color of all these?
Hint:
Five Eyes Riddle
Hint:
Mummy Moving Out 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
Adding Eights Riddle
Hint:
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