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
Chocolate All Year Long
Hint:
Has Two Wheels Riddle
Hint:
A Lions Appetite Riddle
Hint:
Building A Bar Riddle
Roy Smith wanted a new bar. He was such an eccentric old bar owner that he wanted a bar in which all fours walls faced south. After much thought, the builders managed to construct just such a bar. How did they do it?
Hint:
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
Changing The Tp Riddle
Hint:
Cabin On The Mountain Riddle
There is a cabin on the side of a mountain. Three people are inside and they are dead. How did they die?
Hint:
They were killed in a plane crash The three people were the pilot, co-pilot, and navigator. They crashed in snow storm. Did you answer this riddle correctly?
YES NO
YES NO
And Abiding Flame Riddle
Once I could kindle fire;
Now I am cold as ice.
I have forgot desire
Buried in earth's blind vise,
Changed wholly, yet the same,
Wild with abiding flame.
I am?
Now I am cold as ice.
I have forgot desire
Buried in earth's blind vise,
Changed wholly, yet the same,
Wild with abiding flame.
I am?
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
A Disney Princess Riddle
Hint:
The Sister Of Drezilla
I want to marry the prince someday
I have a step sister
I love purple, my sister Drezilla loves green
My mother is Lady Tremaine
I am..?
I have a step sister
I love purple, my sister Drezilla loves green
My mother is Lady Tremaine
I am..?
Hint:
A Fishes Best Friend Riddle
Hint:
Living In China Riddle
I help a human who wants to help her dad,
I give her bad advice walking into camp,
I love doing stuff for my selfish purposes.
Who am I?
Hint:
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