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
Dark But Not A Room With Curtains
I'm sometimes dark but I'm not a room with curtains
I sometimes contain peanut butter but I'm not a sandwich
I'm sometimes melted but I'm not an ice cube
I'm sometimes in cookies but I'm not a raisin
I'm sometimes a bar but I'm not made of metal
I'm sometimes a chip but I'm not made of potato
What am I?
I sometimes contain peanut butter but I'm not a sandwich
I'm sometimes melted but I'm not an ice cube
I'm sometimes in cookies but I'm not a raisin
I'm sometimes a bar but I'm not made of metal
I'm sometimes a chip but I'm not made of potato
What am I?
Hint:
How Many Chocolates Can You Get?
A shop sells 1 chocolate at $1. You can exchange 3 wrappers for 1 chocolate. If you have $15, how many chocolates can you get?
Hint:
15 chocolates with resale. 15 then with 15 wrappers you get 5 more chocolates. With 3 wrappers from the 5 new chocolates you get 1 more chocolate. And with these 1 more wrapper and the remaining 2 wrappers you get 1 more chocolate. Hence you get total 15 + 5 + 1 + 1 = 22 Did you answer this riddle correctly?
YES NO
YES NO
Burns Fat But Saves You Money
Hint:
Traveling A Great Distance
How do you travel a great distance without letting your feet touch the ground, while never leaving it?
Hint:
Fifty One Bicycles
Hint:
The man was playing a poker game and cheated. The bicycles are a type of card. Did you answer this riddle correctly?
YES NO
YES NO
Almost Hit By A Car Riddle
A man walked home after having been out drinking. He walked down the middle of a deserted country road. There were no streetlights to illuminate the road and there was no moonlight. He was dressed all in black. Suddenly a car that did not have its headlights on came racing down the road. At the last moment, the driver of the car saw the man and swerved to avoid him.
How did he manage to see him?
How did he manage to see him?
Hint:
He was returning home in the middle of the day, so anyone could have seen him. Did you answer this riddle correctly?
YES NO
YES NO
Americans In A Pub Riddle
There were two Americans sitting in a British Pub. One of them was the father of the other one's son. How could this be so?
Hint:
How Many Spaces Riddle
Hint:
64; the space that comes after the 64th spoke, would be the first spoke. Did you answer this riddle correctly?
YES NO
YES NO
Add Up To 100 Riddle
With the numbers 123456789, make them add up to 100. They must stay in the same order. You can use addition, subtraction, multiplication, and division. Remember, they have to stay in the same order!
Hint:
A Farmers Sheep Riddle
Hint:
Farmer Stones Riddle
A farmer had a stone that he used to measure grain on his scale. One day his neighbor borrowed the stone, and when he returned, it was broken into four pieces. The neighbor was very apologetic, but the farmer thanked the neighbor for doing him a big favor. The farmer said that now he can measure his grain in one pound increments starting at one pound all the way to forty pounds (1, 2, 3, 17, 29, 37, etc.) using these four stones.
How much do the four stones weight?
How much do the four stones weight?
Hint:
The stones weight 1 pound, 3 pounds, 9 pounds and 27 pounds. These can be used in combination with each other on both sides of the scale to come up with any counterweight from 1 to 40 pounds. 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:
Apples In A Basket Riddle
There are four girls, and four apples in a basket. Every girl takes an apple, yet one apple remains in the basket? How is this possible?
Hint:
The answer is that one girl took the basket. She took the last apple while it was in the basket. Did you answer this riddle correctly?
YES NO
YES NO
Holes On Holes Riddle
I have holes on the top and bottom. I have holes on my left and on my right. And I have holes in the middle, yet I still hold water. What am I?
Hint:
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