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
Benzene Ring Riddle
Hint:
A Boomerang Riddle
Hint:
Egg In A Glass Riddle
A science teacher told his after school class, "Whoever can get this egg into this smaller glass bottle will win no homework for a week! The rules are: the egg has to go into the bottle in one piece, and you can't break the bottle. You can also use anything in the science lab. So, do we have any volunteers?"
A boy raised his hand and the teacher pointed at him. The boy took the egg and looked around the science lab for the things he could use. He saw some writing paper, a pack of matches, some vinegar, a sink, and the glass bottle. By the end of the after school class, the boy had gotten the egg into the smaller bottle.
How did he do it?
A boy raised his hand and the teacher pointed at him. The boy took the egg and looked around the science lab for the things he could use. He saw some writing paper, a pack of matches, some vinegar, a sink, and the glass bottle. By the end of the after school class, the boy had gotten the egg into the smaller bottle.
How did he do it?
Hint: Without doing anything to the egg, the egg can't fit into the bottle
First, soak the egg in the vinegar which softens the shell without compromising the egg. Next, take some of the writing paper and shred it into pieces. Take the shredded pieces and put them into the glass bottle. Take a match and light a fire inside the bottle with the shredded paper. After, take the vinegar-soaked egg and put it on the top of the bottle so no oxygen can get into the bottle. The fire can't live without any oxygen so it will try to suck oxygen from the entrance which the egg is blocking. When the fire does this, the fire becomes like a vacuum. So, basically, the fire sucks the egg into the bottle to try to get the oxygen. After a short while, the shell will reharden and that's how the egg got into the bottle. Did you answer this riddle correctly?
YES NO
YES NO
Winter Bird Riddle
Hint:
A Bear With No Teeth
Hint:
The Black Alaskan Dog Riddle
Hint:
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