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
20 Apples Riddle
There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?
Hint:
Pouring Your Drink Riddle
Despite what theyre called
They dont cover your eyes
You fill them with drink
And then maybe some ice.
What could they be?
They dont cover your eyes
You fill them with drink
And then maybe some ice.
What could they be?
Hint:
It Was Murder Riddle
A body is found at the bottom of a multistory building. Seeing the position of the body it is evident that the person jumped from one of the windows.
A homicide detective is called to look after the case. He goes to the first floor and walks in the room facing the direction in which the body was found. He opens the window in that direction and flips a coin towards the floor.
Then he goes to the second floor and repeats the process. He keeps on doing it till the last floor. Then, when he climbs down, he tells the team that it is a murder not suicide.
How did he come to know that it was a murder?
A homicide detective is called to look after the case. He goes to the first floor and walks in the room facing the direction in which the body was found. He opens the window in that direction and flips a coin towards the floor.
Then he goes to the second floor and repeats the process. He keeps on doing it till the last floor. Then, when he climbs down, he tells the team that it is a murder not suicide.
How did he come to know that it was a murder?
Hint:
At each floor, he did the same task of opening the window and flipping the coin. If it was a suicide, then at least the window at any of the floors must have been left open by the person who jumped off. The situation only suggests that someone pushed him off and then closed the window again. Did you answer this riddle correctly?
YES NO
YES NO
Japanese Ship Thief Riddle
A Japanese ship was en route in the open sea. The Japanese captain went for a shower removing his diamond ring and Rolex watch on the table. When he returned, his valuables were missing. The captain immediately called the five suspected crew members and asked each one where and what he was doing for the last 15 minutes.
The Filipino cook in a heavy overcoat said, I was in fridge room getting meat for cooking.
The Indian Engineer with a torch in hand said, I was working on generator engine.
The Sri Lankan seaman said, I was on the mast (top of the ship) correcting the flag which was upside down by mistake.
The British radio officer said, I was messaging to company that we are reaching the next port in 72 hours. From now that is Wednesday morning at 10 AM.
The British navigation officer said, I am on night watch, so sleeping in my cabin.
The captain caught the liar. So who is the thief?
The Filipino cook in a heavy overcoat said, I was in fridge room getting meat for cooking.
The Indian Engineer with a torch in hand said, I was working on generator engine.
The Sri Lankan seaman said, I was on the mast (top of the ship) correcting the flag which was upside down by mistake.
The British radio officer said, I was messaging to company that we are reaching the next port in 72 hours. From now that is Wednesday morning at 10 AM.
The British navigation officer said, I am on night watch, so sleeping in my cabin.
The captain caught the liar. So who is the thief?
Hint:
The thief is the Sri Lankan seaman. They are on a Japanese ship, so it will bear a Japanese flag. The Japanese flag will look the same upside down. Did you answer this riddle correctly?
YES NO
YES NO
Women In The Morning Riddle
Hint:
Ida's Microwaved Coffee Riddle
Ida puts her coffee into the microwave, as she does every morning, for exactly two minutes. When the microwave goes off, she opens the door, but then closes the door again and sets the microwave for two more seconds. What good would two more seconds be?
Hint:
To rotate the handle on the mug so she can comfortably remove it. Did you answer this riddle correctly?
YES NO
YES NO
Dearth In Ireland Riddle
Hint:
Like An Indian Riddle
What has two legs like an Indian, two eyes like an Indian, two hands like an Indian, looks just like an Indian but is not an Indian?
Hint:
Vampire Savings Riddle
Hint:
The Detective Trap Riddle
Detective Sara Dunts was called in for an investigation on a Saturday morning. Mr. John Gooding had mysteriously vanished from his one story home, Sara was told. "I'll phone Mrs. Glen, the caretaker, and get you the address." Detective Chad Sandlers, Sara's partner, said. Sara stood waiting as he made the call. "Okay, everything's set. Mrs. Glen will be expecting you in half an hour at 232 Parker At." Detective Chad said.
Sara hopped out of her car and walked up the long path that led to the house. Right away she was ushered inside by Mrs. Glen. "Detective, I'm so glad you came. The last place I saw Mr. Gooding was in his room. I suspected that would be your first question." Mrs. Glen said somewhat nervously. She walked Sara into the other room. "Up here," Mrs. Glen called from a twisting flight of stairs. The front door banged shut just as Sara started up the steps. "Oh, I must have left the door open. The wind must have shut it." Mrs. Glen said. Again they started up the stairs.
They walked up the enormous stairway. Halfway up detective Sara noticed a weather vane through the window. She realized that the wind was blowing west and in order for it to have shut the door it would have to have been blowing east. Then Sara realized for the first time that there was a third set of footsteps on the stairs. Then it dawned on her and she realized she had walked into a trap. How did Sara know she had walked into a trap?
Sara hopped out of her car and walked up the long path that led to the house. Right away she was ushered inside by Mrs. Glen. "Detective, I'm so glad you came. The last place I saw Mr. Gooding was in his room. I suspected that would be your first question." Mrs. Glen said somewhat nervously. She walked Sara into the other room. "Up here," Mrs. Glen called from a twisting flight of stairs. The front door banged shut just as Sara started up the steps. "Oh, I must have left the door open. The wind must have shut it." Mrs. Glen said. Again they started up the stairs.
They walked up the enormous stairway. Halfway up detective Sara noticed a weather vane through the window. She realized that the wind was blowing west and in order for it to have shut the door it would have to have been blowing east. Then Sara realized for the first time that there was a third set of footsteps on the stairs. Then it dawned on her and she realized she had walked into a trap. How did Sara know she had walked into a trap?
Hint:
Detective Sara Dunts realized she had walked into a trap when she heard the extra set of footsteps. Hearing the footsteps on the stairs made her remember what her partner had said, "Mr. John Gooding had mysteriously vanished from his one story home." She then realized that this was not Mr. Goodings home because at that very moment she realized that she was climbing stairs in a supposedly one story house. Sara immediately called for backup and arrested Mrs. Glen. She then walked down the stairs to find Mr. Gooding near the bottom. The two had planned on kidnapping and killing Sara for putting Mr. Goodings niece and Mrs. Glens son in jail for murder. Both went to jail to serve their time. Did you answer this riddle correctly?
YES NO
YES NO
Everyone Wants More Riddle
Everyone wants more of it to feel special, and to have more of it opens the door to more opportunity. What is it?
Hint:
Banks With No Money Riddle
What has 4 eyes and can not see? Has banks but no money to spend? Runs through the south, but has no legs?
Hint:
Older Than Obama Riddle
What is older than Obama, sits still as stone, but in some people's eyes is more appreciated than the president's home ?
Hint:
Hearing Without Seeing Riddle
Hint:
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