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
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:
Coffee On The Titanic
Hint:
Letters In A Lightning Storm
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
The Missing Captain Riddle
Hint:
Ocean Shopping Riddle
Hint:
Leaving A Port Riddle
You will need this type of transport
To be able to leave a port
You can then float upon the water
And cast nets for fish to be caught
What am I?
To be able to leave a port
You can then float upon the water
And cast nets for fish to be caught
What am I?
Hint:
A Wheel But No Car Riddle
I have a deck but no backyard
I have a bow but no arrows
I have a wheel but Im not a car
I have a beam but Im not a light
I have a stern but Im not serious
I have a crows nest but there are no birds
I am a?
I have a bow but no arrows
I have a wheel but Im not a car
I have a beam but Im not a light
I have a stern but Im not serious
I have a crows nest but there are no birds
I am a?
Hint:
The Pilgrims Aboard This Ship Riddle
Hint:
Blossoming Ship Riddle
Managing to sail this ship
Across the ocean was awesome
The ship that the pilgrims sailed
Was named as though it might blossom Body parts remaining: 6
Across the ocean was awesome
The ship that the pilgrims sailed
Was named as though it might blossom Body parts remaining: 6
Hint:
Sinking Ship Riddle
On a fine sunny day a ship was in the harbor. All of a sudden the ship began to sink. There was no storm and nothing wrong with the ship yet it sank right in front of the spectators eyes.
What caused the ship to sink?
What caused the ship to sink?
Hint:
The Ship Thief Riddle
A Japanese ship is on route back to the shore from the Atlantic Ocean. Seeking the silent waves, the captain decides to take a shower. He keeps his Rolex and diamond studded gold bracelet on the shelf and goes for a shower. When he returns back, he finds both the watch and bracelet missing. He immediately calls the four crew members and asks them what they were doing during that duration. Following are the answers:
1. French Guy, the Cook: I was in the kitchen, making bacon sandwiches for everybody.
2. Russian Guy, the engineer: I was in the generator room, checking the generator.
3. Pakistani Guy, the housekeeper: I saw that the flag hoisted on the ship was upside down, so I went to correct it.
4. Srilankan Guy, the second housekeeper: I was tired and taking a quick nap.
The captain immediately knew who the thief was. Can you tell?
1. French Guy, the Cook: I was in the kitchen, making bacon sandwiches for everybody.
2. Russian Guy, the engineer: I was in the generator room, checking the generator.
3. Pakistani Guy, the housekeeper: I saw that the flag hoisted on the ship was upside down, so I went to correct it.
4. Srilankan Guy, the second housekeeper: I was tired and taking a quick nap.
The captain immediately knew who the thief was. Can you tell?
Hint:
The thief is the Pakistani guy. It is because the flag of Japan looks same when upside down and no one can tell if it is upside down. So, he was telling a lie. Did you answer this riddle correctly?
YES NO
YES NO
Vampires Crossing The Sea
Hint:
The Sick Ship Riddle
Hint:
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