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
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:
Who Stole The Money Riddle
A man placed a $100 dollar bill on his desk and left for work. When he returned back the money was gone. He has three suspects: the cook, the maid and the electrician.
The cook said he put the bill under a book on his desk to keep it safe. The man checked and it is no longer there.
The maid said she moved the bill to the inside of the book between page 1 and 2 while she was cleaning. Again, the man checked the book and there was nothing between page 1 and 2.
The electrician said he saw the bill sticking out of the book and he moved it between page 2 and 3 to keep it safe.
Who stole the money?
The cook said he put the bill under a book on his desk to keep it safe. The man checked and it is no longer there.
The maid said she moved the bill to the inside of the book between page 1 and 2 while she was cleaning. Again, the man checked the book and there was nothing between page 1 and 2.
The electrician said he saw the bill sticking out of the book and he moved it between page 2 and 3 to keep it safe.
Who stole the money?
Hint:
The electrician stole the money.
If the man checked for the money between page 1 and 2 of the book, then page 2 and 3 will be opposite sides of a single page and will not be able to hold the money.
Did you answer this riddle correctly?
YES NO
If the man checked for the money between page 1 and 2 of the book, then page 2 and 3 will be opposite sides of a single page and will not be able to hold the money.
Did you answer this riddle correctly?
YES NO
The 100th Floor Riddle
A man lives on the 100th floor of his apartment building. Every day he takes the elevator down from his apartment to the lobby. After work, he takes the elevator from the lobby to the 50th floor and walks up the stairs the rest of the way. On rainy days he takes the elevator all the way from the lobby to the 100th floor. Why?
Hint:
The man was a dwarf. On rainy days he had an umbrella to help him press the button 100. Did you answer this riddle correctly?
YES NO
YES NO
Songs About My River Riddle
Thomas Edison was born here. Olivia Newton John sang about the banks of my river. I contain the Rock and Roll Hall of Fame. What state am I?
Hint:
Stealing Icebergs Riddle
Hint:
Stealing Duck Riddle
Hint:
Solved: 76%
The Stupid Pianist Riddle
Hint:
The Start Of Nothing Logic Riddle
Hint: It's in plain sight
It Follows A River While Standing Still
Hint:
The 100 Pound Watermelon
How much water evaporated?
Hint:
50 pounds.
In the beginning it is 99 pounds water and 1 pound other stuff. At the end the 1 pound other stuff is 2 percent so the total weight is 50 pounds. 50 pounds - 1 pound other stuff = 49 pounds water. So 99 pounds - 49 pounds = 50 pounds water lost. Did you answer this riddle correctly?
YES NO
In the beginning it is 99 pounds water and 1 pound other stuff. At the end the 1 pound other stuff is 2 percent so the total weight is 50 pounds. 50 pounds - 1 pound other stuff = 49 pounds water. So 99 pounds - 49 pounds = 50 pounds water lost. Did you answer this riddle correctly?
YES NO
Stuck With Me Forever Riddle
Your finger fits right in it. You play with it when you're bored. Once you're married, you're stuck with the same one forever. What is it?
Hint:
A One Way Street
A girl who was just learning to drive went down a one-way street in the wrong direction, but didn't break the law. How come?
Hint:
Presidents Of The United States Riddle
The 22nd and 24th presidents of the United States of America had the same parents, but were not brothers. How can this be possible?
Hint:
They were the same man. Grover Cleveland served two terms as president of the United States, but the terms were not consecutive. Did you answer this riddle correctly?
YES NO
YES NO
What Is Brown And Sticky
Hint:
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