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
4th Of July Riddle
Hint:
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:
Murdered On A Sunday Afternoon
Maid: I was fixing the table.
Cook: I was cooking breakfast.
Butler: I was polishing the silverware and the dishes.
Gardener: I was planting tomato seeds.
Wife: I was reading a book.
Who did it?
Hint:
The cook did it. You don't cook breakfast in the afternoon. Did you answer this riddle correctly?
YES NO
YES NO
Camping On Sunday Riddle
A man went on a camping trip on his horse. He left on Sunday and came back on Sunday but he went away for 10 days. How can this be?
Hint:
The Dogwood Tree Riddle
Hint:
A List Of Names Riddle
Lennie was cleaning up some old papers in his office and found a list with the following names:
Washington
Jefferson
Lincoln
Hamilton
Jackson
Grant
The last name on the list was mostly worn away and he couldnt make it out. What was the last name and why?
Washington
Jefferson
Lincoln
Hamilton
Jackson
Grant
The last name on the list was mostly worn away and he couldnt make it out. What was the last name and why?
Hint:
Franklin. Its a list of the men on U.S. currency, $1, $2, $5, $10, $20 and $50. The $100 bill has Franklin. And an interesting tidbit is that Hamilton, along with Franklin, are the only two men in the list who did not serve as president. Did you answer this riddle correctly?
YES NO
YES NO
100 Widgets Riddle
Hint:
It would take 5 minutes. Each machine takes 5 minutes to make its widget. Therefore, each of the 100 machines would have finished making its widget in 5 minutes. Did you answer this riddle correctly?
YES NO
YES NO
Stronger Days Riddle
Hint:
100 Meter Sprint Riddle
Hint:
Running Men And Dogs Riddle
Hint:
100 Lawyers Riddle
Hint:
A Dog In July Riddle
Hint:
Dogs And Trees Riddle
Hint:
Less Than 100 Riddle
Find a number less than 100 that is increased by one-fifth of its value when its digits are reversed.
Hint:
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