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
Help Catch A Mouse Riddle
This is a kind of animal
You might see in someones house
Because they are a common pet
That might help to catch a mouse
What is it?
You might see in someones house
Because they are a common pet
That might help to catch a mouse
What is 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:
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 Man In The Shadows Riddle
Hint:
Pick A Room Riddle
It is Halloween and your friends dare you to go into a haunted house. You creep up to the door, a little scared wondering what is behind the door. You go in and there is a long hallway leading out into a dark musty room with three doors.
You're kind of scared once you are inside. You try to turn back, to get back outside, but when you turn around the door is closed and locked. You yell for help but there is only silence. The room is dark and you look for a light source. You see a light switch and try to turn it on. Sadly the power is out. You are terrified but have no choice but to follow the long hallway to the three doors in the pitch black.
Behind one door is a bottomless pit with no end. Behind another door is an electric chair which you must sit in. Behind the last door is a pool full of acid. You must go in one of the rooms to the danger. Which one should you go through?
You're kind of scared once you are inside. You try to turn back, to get back outside, but when you turn around the door is closed and locked. You yell for help but there is only silence. The room is dark and you look for a light source. You see a light switch and try to turn it on. Sadly the power is out. You are terrified but have no choice but to follow the long hallway to the three doors in the pitch black.
Behind one door is a bottomless pit with no end. Behind another door is an electric chair which you must sit in. Behind the last door is a pool full of acid. You must go in one of the rooms to the danger. Which one should you go through?
Hint:
You should definitely go through the electric chair. Since the power is out, when you sit in the electric chair it will have no effect on you. Did you answer this riddle correctly?
YES NO
YES NO
Green And Red Apple Trees Riddle
One of the apple trees had only green apples, and the other tree had only red apples. The village boys picked all the apples from both trees, and found that there were 5 red apples for every 4 green apples. Between them, the boys then ate 16 red apples and 16 green applies. When they counted the apples that were left, they found there were 3 red apples for every 2 green apples. How many apples of each color were on the trees in the first place?
Hint:
Savor The Flavor Riddle
Discovered in Africa, I spread like a tide to become a hot staple known the world wide.
A necessity to some, a treasure to many, I'm best enjoyed among pleasant company.
Some take me straight, while some like to savor, my essence to which has been added a flavor.
So put down your cares and sit awhile with me; I'll send you back refreshed and full of energy.
What am I?
A necessity to some, a treasure to many, I'm best enjoyed among pleasant company.
Some take me straight, while some like to savor, my essence to which has been added a flavor.
So put down your cares and sit awhile with me; I'll send you back refreshed and full of energy.
What am I?
Hint: This doesn't need a hint, but in case you peeked: I'll have a grande latte!
Coffee. It was first discovered in the area of Africa now called Ethiopia. Legend has it that a goat herder observed his goats acting unusually frisky after eating berries from a bush. When he tried them himself, his energy was renewed. And the rest is history. Did you answer this riddle correctly?
YES NO
YES NO
Farmer Joe's Container Riddle
Farmer Joe was cleaning out his big old dusty farm shed. He dragged out an old water container which was full of old dirty water and it weighed 5 kilograms. Joe put something in the container and then it weighed less. What did he put in the container?
Hint:
The Locked Away Princess Riddle
A princess was locked in a tower with four yards of pure brick for the ceiling, floors, and walls. There were no windows or doors at all, no way to get out.
She turned the knob to take a bath. When she notices the tub getting full, she tried to turn the knob, but it's stuck!
How does she avoid drowning?
She turned the knob to take a bath. When she notices the tub getting full, she tried to turn the knob, but it's stuck!
How does she avoid drowning?
Hint:
I Have A Source Riddle
I have a source but Im not a journalist
I have a delta but Im not a Greek alphabet
I have banks on both sides of me but Im not surrounded by money
I flow but Im not a bloodstream
Im full of water but Im not a fish tank
What am I?
I have a delta but Im not a Greek alphabet
I have banks on both sides of me but Im not surrounded by money
I flow but Im not a bloodstream
Im full of water but Im not a fish tank
What am I?
Hint:
21 Jars Riddle
You have 21 jars with you. Out of them, 7 are filled with water, 7 are half-full with water and 7 are empty. How will you distribute the jars among three people such that each one of them gets the equal number of jars and equal amount of water?
Hint:
Give 3 full, 1 half-full and 3 empty bottles to the first person.
Give 3 full, 1 half-full and 3 empty bottles to the second person.
Give 1 full, 5 half-full and 1 empty bottle to the third person. Did you answer this riddle correctly?
YES NO
Give 3 full, 1 half-full and 3 empty bottles to the second person.
Give 1 full, 5 half-full and 1 empty bottle to the third person. Did you answer this riddle correctly?
YES NO
Threw Away The Outside Food Riddle
First I threw away the outside and cooked the inside, then I ate the outside and threw away the inside, what did I eat?
Hint: It's a vegetable
Condemned To Death Riddle
A murderer is condemned to death.
He has to choose between three rooms.
-The first is full of raging fires
-The second is full of assassins with loaded guns
-The third is full of lions that havent eaten in 3 years.
Which room is safest for him?
He has to choose between three rooms.
-The first is full of raging fires
-The second is full of assassins with loaded guns
-The third is full of lions that havent eaten in 3 years.
Which room is safest for him?
Hint: When's the last time you ate?
The 3rd one because the lions should have died after not eating for 3 years. Did you answer this riddle correctly?
YES NO
YES NO
Invited To Dinner Riddle
A few days ago, I was invited to dinner at a friend's house. The strange thing is, my friend recently got involved with some weird religious cult. While I was there, he served up some type of meat, but he wouldn't tell me what kind of meat it was. It kind of freaked me out. For a second, I wondered if it was human meat, but then, after I ate it, I knew it definitely wasn't human meat.
What's really going on?
What's really going on?
Hint:
The guy who was invited over was a cannibal. How else would he have known it wasn't human meat if he'd never had human meat to begin with? Did you answer this riddle correctly?
YES NO
YES NO
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