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?
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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
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?
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YES NO
Late For The Bus Riddle
A married couple is traveling by bus on dangerous mountain roads. Midway through their journey the bus stops for snacks and a restroom break. The couple is enjoying the postcards in the store when the bus driver curtly tells them its past time to leave. Fifteen minutes after, the bus is hit by a mud slide and two people are killed. The couple blames themselves for the deaths. Why?
Hint:
They blame themselves because they caused the bus to be late. If they had been on time, the bus would have already passed the location of the mud slide. Did you answer this riddle correctly?
YES NO
YES NO
Six Foot Fishing Pole Riddle
A boy goes and buys a fishing pole that is 6 3 long. As he goes to get on the bus, the bus driver tells him that he cant take anything on the bus longer than 6. The boy goes back to town, buys one more thing, and the bus driver allows him on the bus. What did he buy and what did he do with it?
Hint:
Killed Her Own Sister Riddle
A woman killed her own sister. During the interrogation, she told a story that she had just attended her own mother's funeral a few days before the crime took place. While at the funeral, she said that she met a guy whom she did not know. She thought this guy was amazing, so much her dream guy that she believed him to be just that! She fell in love with him right there, but never asked for his number and could not find him. A few days later, she killed her sister.
Although this woman has confessed to the crime, police are still intrigued by the story, especially because she won't tell them her motive. Hearing this tragic story, with his psychological education background, Detective Thompson easily guessed the woman's motive.
Why did the woman killed her own sister?
Although this woman has confessed to the crime, police are still intrigued by the story, especially because she won't tell them her motive. Hearing this tragic story, with his psychological education background, Detective Thompson easily guessed the woman's motive.
Why did the woman killed her own sister?
Hint:
She was hoping that the guy would appear at the funeral again. Did you answer this riddle correctly?
YES NO
YES NO
High Performance MAC Riddle
A high performance MAC and and a high performance IBM are in a store display window. A customer walks into the store. Which one does he choose?
Hint:
The high performance IBM. There is no such thing as a high performance MAC. Did you answer this riddle correctly?
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YES NO
Captured By The Riddler
In the land of Geopolizza, three men were captured by the infamous Riddler. So, the Riddler buries the three men, named 1, 2 and 3 in such a manner, that 1 is in the front, 2 in the middle and 3 in the back. They are buried neck deep, and cannot move, not even their heads. He shows them 5 caps, two of which are red and 3 of them are white. He then switches off the lights and places a hat on top of their heads. The situation is such that no one can see their hat color, 1 is facing the wall and cant say anything, 2 can see 1 and 3 can see both 1 and 2. Then he tells the rules of his game: "If either of you three can tell the correct color of your head, I will let all of you go. However, if any of you answer wrong, all 3 of you will instantly die. Time is 3 minutes."
Upon 2 and half minutes passing, A shouts the answer and all 3 are released free. How did he know the correct answer ?
Upon 2 and half minutes passing, A shouts the answer and all 3 are released free. How did he know the correct answer ?
Hint:
P3 can only be certain of his cap if 1 & 2 are both white. Since he is not certain then 1 & 2 must be either white/red or red/red. 2 knows this but the only combination that he will be able to know the colour of his own cap is if he sees that 1 is wearing a white cap. 1 knows this but as 2 remains uncertain then 1 must be wearing a red cap. Did you answer this riddle correctly?
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YES NO
The King And The Kingdom Riddle
Once there lived a king who did not allow anybody to leave the kingdom and any foreigners in his kingdom. There was only one bridge that connected his empire with the outer world. A guard who was a sharpshooter was specially assigned for a lookout on the bridge. According to the orders, anyone moving outside should be killed and anyone coming to his kingdom should be sent back. To take rest, the guard used to sit inside his hut for 5 minutes and return back on the lookout. The bridge took a minimum of 8 minutes to pass.
Even then, a woman was able to escape the kingdom without incurring any kind of harm to the guard.
How ?
Even then, a woman was able to escape the kingdom without incurring any kind of harm to the guard.
How ?
Hint:
The woman started walking across the bridge when the guard was inside the hut. She walked all the time he was inside (5 minutes) and then turned and moved back towards the kingdom. On approaching the kingdom he was asked for papers and since she did not have any, she was sent back. Did you answer this riddle correctly?
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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?
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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?
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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?
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YES NO
The Table Tennis Ball
A table tennis ball fell into a tight deep pipe. The pipe was only a bit wider then the ball, so you can not use your hand. How would you take it out, with no damage?
Hint:
Pour some water into the pipe so that the ball swims up on the surface. Did you answer this riddle correctly?
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YES NO
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