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
The Odds Of A Boy Riddle
Mr. Smith has two children. If the older child is a boy, what are the odds that the other child is also a boy?
Hint:
Spell Sexy Riddle
Hint:
Weight From A Barrel Riddle
Hint:
Tea Cups On The Table
Hint: Try reading the question out loud.
The answer is 3 tea cups because the question was not forty cups it was four tea cups. Did you answer this riddle correctly?
YES NO
YES NO
A Boy Who Talks To Animals
I lived in London
I wear a yellow dress
I go to Africa to study gorillas
I met a boy who talks to the animals
Who am I?
I wear a yellow dress
I go to Africa to study gorillas
I met a boy who talks to the animals
Who am I?
Hint:
Dialing 911 Riddle
An old lady in the United States has a heart attack and dials 911. No one came and she died. How could this have happened?
Hint:
A Boy Born In May Riddle
How could a boy be born in May, although his birthday was in June, and then grow up and marry his mother?
Hint:
He could be born in the month of June in a town called May. When he grows up, he could officiate his mother's wedding and "marry" her to someone else. Did you answer this riddle correctly?
YES NO
YES NO
Coffee Diner Riddle
A man walks into a diner and sits down. There's a new waitress working that he's never seen before. When she comes to his table to take his order, he says "Just a cup of coffee please." A few minutes later the waitress brings the man his coffee and heads back to the kitchen. A short while later, the man notices that there is a fly in his coffee and calls the waitress back. He asks her nicely to bring him another cup. The waitress brings the man's cup of coffee back to the kitchen and returns a few moments later. "Here you are, I poured you a new cup of coffee, no fly this time" she says and hands him the cup. The waitress turns around and starts to head back to the kitchen. She only takes a few steps before she hears the man shout out "Hey, this is the same cup of coffee, all you did was remove the fly!"
Assuming the coffee was still hot, how did the man know it was the same cup of coffee?
Assuming the coffee was still hot, how did the man know it was the same cup of coffee?
Hint: A man walks into a diner and sits down. There's a new waitress working that he's never seen before. When she comes to his table to take his order, he says "Just a cup of coffee please." A few minutes later the waitress brings the man his coffee and heads
Because the coffee was sweet. The man had added sugar to his coffee before noticing the fly. When the waitress brought him the "new" cup of coffee, he took a sip (to check whether it was in fact a newly poured cup of coffee) and noticed that the coffee was "already" sweet. Did you answer this riddle correctly?
YES NO
YES NO
Five Weeks Old Riddle
Born at the same time as the world, destined to live as long as the world, and yet never five weeks old. What is it?
Hint:
The Boy Snake Riddle
Hint:
The Bats Boyfriend Riddle
Hint:
How Many Months?
Hint:
Simba's Girlfriend Riddle
Hint:
The Riddle Of Legs
Hint:
The answer to all three is a baby. True, it crawls on all fours, but cut off its legs and it can only wiggle on two limbs. Give it a crutch, it can hobble around on three. Did you answer this riddle correctly?
YES NO
YES NO
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