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
Anonymous Phone Call Riddle
Acting on an anonymous phone call, the police raid a house to arrest a suspected murderer. They dont know what he looks like but they know his name is John and that he is inside the house. The police bust in on a carpenter, a lorry driver, a mechanic and a fireman playing cards. Without hesitation or communication of any kind, they immediately arrest the fireman. How do they know theyve got their man?
Hint:
The fireman is the only man in the room. The rest of them are women. Did you answer this riddle correctly?
YES NO
YES NO
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
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
Vampire Holiday Riddles
Hint:
Pills A And B Riddle
You have two bottles of pills marked with the label A and B. The pills are identical. The doctor has asked you to take one A pill and one B pill daily. You cant take more or less than that.
While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.
You cant throw away the expensive pills. What will you do now?
While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.
You cant throw away the expensive pills. What will you do now?
Hint:
Cut each of the three pills in half and put each half in two piles. Now, each of the two piles will contain half of pill A and two halves of pill B.
Take one pill A and cut into half and put the two halves in the two piles. Now, each pile will have two halves of pill A and two halves of pill B which means one pill A and one pill B. You can take one pile today and one pile the next day. Did you answer this riddle correctly?
YES NO
Take one pill A and cut into half and put the two halves in the two piles. Now, each pile will have two halves of pill A and two halves of pill B which means one pill A and one pill B. You can take one pile today and one pile the next day. Did you answer this riddle correctly?
YES NO
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
A Game Of Dodge Ball Riddle
If the order of throwing is you, John, then Tom; what should you do to have the best chance of winning?
Hint:
Miss the first time on purpose.
If you try to hit John and do. Then Tom goes next and he will hit you and you will lose for sure. If you aim at Tom and hit him then John will go for you. If you miss on your first turn John will go for Tom for sure because he is a stronger player. If he hits him then it's just you and John, but you are going first. If he misses him then Tom will hit John and it will be just you and Tom, but again in this case you are going first. Did you answer this riddle correctly?
YES NO
If you try to hit John and do. Then Tom goes next and he will hit you and you will lose for sure. If you aim at Tom and hit him then John will go for you. If you miss on your first turn John will go for Tom for sure because he is a stronger player. If he hits him then it's just you and John, but you are going first. If he misses him then Tom will hit John and it will be just you and Tom, but again in this case you are going first. Did you answer this riddle correctly?
YES NO
One Snowy Night Riddle
One snowy night, Sherlock Holmes was in his house sitting by a fire. All of a sudden a snowball came crashing through his window, breaking it. Holmes got up and looked out the window just in time to see three neighborhood kids who were brothers run around a corner.
Their names were John Crimson, Mark Crimson and Paul Crimson. The next day Holmes got a note on his door that read ? Crimson. He broke your window. Which of the three Crimson brothers should Sherlock Holmes question about the incident?
Their names were John Crimson, Mark Crimson and Paul Crimson. The next day Holmes got a note on his door that read ? Crimson. He broke your window. Which of the three Crimson brothers should Sherlock Holmes question about the incident?
Hint:
He should question Mark Crimson.
? = question MARK, so the note on the door reads Question Mark Crimson. He broke your window. Did you answer this riddle correctly?
YES NO
? = question MARK, so the note on the door reads Question Mark Crimson. He broke your window. Did you answer this riddle correctly?
YES NO
The House Of Seeing
Hint:
There is a house. One enters it blind and leaves it seeing. What is it? Did you answer this riddle correctly?
YES NO
YES NO
Locked In A Room
Rooney was locked in a room by kidnappers.
All that is in the room is a piano, calendar, and a bed. The room is locked from the outside.
What does he eat, drink, and how does he escape and get out?
All that is in the room is a piano, calendar, and a bed. The room is locked from the outside.
What does he eat, drink, and how does he escape and get out?
Hint:
Rooney eats the 'dates' on the calendar, gets water from the waterbed, and uses the piano key to escape. Did you answer this riddle correctly?
YES NO
YES NO
Out For Pizza Riddle
A group of ten people are going out for pizza but only two of them have an umbrella to keep them dry. But they manage to walk all the way to the pizza place without getting wet.
How is this possible?
How is this possible?
Hint:
The Barrel With No Lid
There is a barrel with no lid and some beer in it. "This barrel is more than half full," said Chuck. "No it's not," say Joe. "It's less than half full." Without any measuring implements and without removing any beer from the barrel, how can they easily determine who is correct?
Hint:
They must tilt the barrel until the beer reaches the rim of the barrel. If they can see the bottom of the barrel then it is less than half full. Did you answer this riddle correctly?
YES NO
YES NO
Three Switches Riddle
Three switches outside a windowless room are connected to three light bulbs inside the room. How can you determine which switch is connected to which bulb if you are only allowed to enter the room once?
Hint:
Switch on the first switch, leave it for a minute, and then switch it off again. Then switch on the second switch and enter the room. The second switch will be connected to the light that is on, the first switch will be connected to the light with the warm bulb, and the third switch will be connected to the light with the cold bulb. Did you answer this riddle correctly?
YES NO
YES NO
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