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:
Who Killed The Old Man Riddle
An old man lives alone in a house. Because of his age, he is not able to move comfortably and hence most of the things used to be delivered to his house.
On Friday while delivering the mail, the postman feels something suspicious in the house and tries to look inside through the key hole and he saw the blood filled body of the old man.
The police arrived the scene.
Outside the house, he found two bottles of warm milk, Tuesday newspaper, some unopened mail, and some gifts.
The police wasted no time to find the murderer.
Who killed the old man?
On Friday while delivering the mail, the postman feels something suspicious in the house and tries to look inside through the key hole and he saw the blood filled body of the old man.
The police arrived the scene.
Outside the house, he found two bottles of warm milk, Tuesday newspaper, some unopened mail, and some gifts.
The police wasted no time to find the murderer.
Who killed the old man?
Hint:
The newspaper delivery man, because there was no Wednesday, Thursday or Friday newspaper. He knew there was no one home to read it! Did you answer this riddle correctly?
YES NO
YES NO
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:
Anonymous Phone Call Riddle
Acting on an anonymous phone call, the police raid a house to arrest a suspected murderer. They dont know what he looks like but they know his name is John and that he is inside the house. The police bust in on a carpenter, a lorry driver, a mechanic and a fireman playing cards. Without hesitation or communication of any kind, they immediately arrest the fireman. How do they know theyve got their man?
Hint:
The fireman is the only man in the room. The rest of them are women. 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
Strawberry Jam Stain Riddle
The Smith family is a very wealthy family that lives in a big, circular home. One morning, Mr. Smith woke up and saw a strawberry jam stain on his new carpet. He figured out that everyone who was there that morning had a jam sandwich. From the following statements, figure out who spilled the jam.
Billy Smith: I was outside playing basketball.
The Maid: I was dusting the corners of the house.
Chef: I was starting to make lunch for later.
Who is lying?
Billy Smith: I was outside playing basketball.
The Maid: I was dusting the corners of the house.
Chef: I was starting to make lunch for later.
Who is lying?
Hint:
The maid was lying. There are no corners in a circular house.
Did you answer this riddle correctly?
YES NO
Did you answer this riddle correctly?
YES NO
Epileptic Chef Riddle
Hint:
She Shot Her Husband Riddle
Hint:
The woman is a photographer. She shot a picture of her husband, developed it and hung it up to dry. Did you answer this riddle correctly?
YES NO
YES NO
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:
Jack And Jill Riddle
Jack and Jill are lying on the floor inside the house, dead. They died from lack of water. There is shattered glass next to them. How did they die?
Hint:
Wall Clock Riddle
My only timepiece is a wall clock. One day I forgot to wind it and it stopped. I went to visit a friend whose watch is always correct, stayed awhile, and returned home. There I made a simple calculation and set the clock right. How did I do this when I had no watch on me to tell how long it took me to return home from my friends house?
Hint:
Before I left, I wound the wall clock. When I returned, the change in time it showed equaled the time it took to go to my friend's and return, plus the time I spent there. But I knew the latter, because I looked at my friend's watch both when I arrived and when I left. Subtracting the time of the visit from the time I was absent from my house, and dividing by 2, I obtained the time it took me to return home. I added this time to the time my friend's watch showed when I left, and set this sum on my wall clock. Did you answer this riddle correctly?
YES NO
YES NO
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
Abandoned Aquarium Riddle
There is an abandoned aquarium in an empty house. The aquarium has three large fish and three small fish. But after a week, one large fish and two small fish die.
How many remain in the aquarium?
How many remain in the aquarium?
Hint:
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:
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