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:
Bike Art Riddle
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:
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
Apples In The Family Riddle
How can you distribute three apples to two fathers and their two sons, giving a whole apple to each?
Hint:
They are Grandfather - Father - Son. The middle is a father and a son at the same time! Did you answer this riddle correctly?
YES NO
YES NO
Sarah's Seven Apples
A doctor and a bus driver are both in love with the same woman, an attractive girl named Sarah. The bus driver had to go on a long bus trip that would last a week. Before he left, he gave Sarah seven apples. Why?
Hint:
Making An Apple Turnover
Hint:
Maggot Stuck In An Apple
Hint:
Perverted Apple Riddle
Hint:
Apple In The Road Riddle
Hint:
Stolen Apple Riddle
Mrs. Stotch is a fifth grade teacher. One of her students took her apple. Mrs. Stotch has narrowed the suspects down to Billy, Paige, and Tyler. Each of the students give these statements:
Billy: I didnt do it.
Paige: I didnt do it.
Tyler: Paige did it!
Mrs. Stotch knows that only one of the kids is telling the truth. Who is telling the truth and who took the apple?
Billy: I didnt do it.
Paige: I didnt do it.
Tyler: Paige did it!
Mrs. Stotch knows that only one of the kids is telling the truth. Who is telling the truth and who took the apple?
Hint:
Billy did it. Paige is telling the truth so she didnt do it. Tyler is lying so he reinforces that Paige didnt do it. Billy is lying so he did it. Did you answer this riddle correctly?
YES NO
YES NO
Half An Apple Riddle
Hint:
Alligator On A Track Riddle
Hint:
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:
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