Outrunning A Train Riddle
Walking home one day, you take a short cut along the train tracks. The tracks cross a narrow bridge over a deep gorge. At the point you are 3/8 of the way across the bridge, you hear the train whistle somewhere behind you. You charge across the bridge, and jump off the track as the train is about to run you down. As it happens, if you had gone the other way, you would have reached safety just before being run over as well. If you can run ten miles per hour, how fast is the train moving?
Hint:
The train is moving at 40 miles per hour. Imagine that a friend is walking with you. When the train whistle blows, you head away from the train, he heads toward it. When he reaches safety, you will be 6/8 (or 3/4)of the way across the bridge, and the train will have just reached the bridge. For the train to cross 4/4 of the bridge in the time you cross the remaining 1/4, the train must be moving four times your speed. Did you answer this riddle correctly?
YES NO
YES NO
Two Girls On A Train
Two schoolgirls were traveling from the city to a dacha (summer cottage) on an electric train.
"I notice," one of the girls said "that the dacha trains coming in the opposite direction passes us every 5 minutes. What do you think-how many dacha trains arrive in the city in an hour, given equal speeds in both directions?"
"Twelve, of course," the other girl answered, "because 60 divided by 5 equals 12."
The first girl did not agree. What do you think?
"I notice," one of the girls said "that the dacha trains coming in the opposite direction passes us every 5 minutes. What do you think-how many dacha trains arrive in the city in an hour, given equal speeds in both directions?"
"Twelve, of course," the other girl answered, "because 60 divided by 5 equals 12."
The first girl did not agree. What do you think?
Hint:
If the girls had been on a standing train, the first girl's calculations would have been correct, but their train was moving. It took 5 minutes to meet a second train, but then it took the second train 5 more minutes to reach where the girls met the first train. So the time between trains is 10 minutes, not 5, and only 6 trains per hour arrive in the city. Did you answer this riddle correctly?
YES NO
YES NO
The Uncharted Island Riddle
A plane containing 5 people crashes into an uncharted island, and all of them survive for a limit of 5 days. 2 of them build themselves graves and die in it from the hard work. 1 person fills one of the graves with dirt and then dies next to it on day 3. The last two people build 3 graves, and put in one of the corpses, but 5 years later, 11 people are not in their graves, yet the graves are full of corpses. How?
Hint:
On day four, the last two survivours(who are different sexes)found food which will last each of them 4 more years, and on the fifth day, they began reproducing. By the fourth year, ten children have been taught how to raise themselves. The children were thoughtful and put their corpses in the grave. Did you answer this riddle correctly?
YES NO
YES NO
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?
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Chocolate All Year Long
Hint:
Billy's Bicycle Riddle
Bill rode his bicycle 300 miles. Three tires were used equally in accumulating this distance. How many miles of wear did each tire sustain?
Hint:
200 miles. For every mile traveled, each of the two tires sustained one mile of usage. Therefore, in a total of 300 miles traveled, there would be a total of 600 miles of wear. And 600 divided by three is 200. Did you answer this riddle correctly?
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YES NO
A Lions Appetite Riddle
Hint:
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:
She Shot Her Husband Riddle
A man and a woman live peacefully in a house together. But one day the woman shoots her husband. Then she holds him under water for over five minutes. Finally, she hangs him, but ten minutes later they go out and enjoy a wonderful dinner. How can this be?
Hint:
The woman is a photographer. She shot a picture of her husband, developed it and hung it up to dry. Did you answer this riddle correctly?
YES NO
YES NO
Cabin On The Mountain Riddle
There is a cabin on the side of a mountain. Three people are inside and they are dead. How did they die?
Hint:
They were killed in a plane crash The three people were the pilot, co-pilot, and navigator. They crashed in snow storm. Did you answer this riddle correctly?
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YES NO
Breakfast And Tea Riddle
People speak through me, yet I do not make a sound.
People can sell me, yet I have many clones.
I can bring you laughter between breakfast and tea,
Yet I can also break your heart easily.
I cover the earth like trees of old,
Whose leaves can blind and yet enfold.
People can sell me, yet I have many clones.
I can bring you laughter between breakfast and tea,
Yet I can also break your heart easily.
I cover the earth like trees of old,
Whose leaves can blind and yet enfold.
Hint:
A book. Authors can speak to you through a book, yet the book makes no sound. Books are sold and have many duplicate copies. A book can bring the reader to tears and laughter, they span the globe and the leaves of a book (a single sheet in a book is called a leaf) can get you wrapped up in the story that youre unaware of whats going on around you. Did you answer this riddle correctly?
YES NO
YES NO
Driven Through The Day Riddle
People are driven through the day by me
Late nights I do inspire
If not contained I run wild
What am I?
Late nights I do inspire
If not contained I run wild
What am I?
Hint:
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?
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YES NO
The Bus Stop Riddle
An empty bus pulls up at a stop and 5 people get on. At the next stop 5 people get off and twice as many people get on as at the first stop. At the third stop 10 people get off.
How many people are on the bus at this point?
How many people are on the bus at this point?
Hint:
Ne, the bus driver.
On the 1st stop, 5 people get on. On the 2nd stop, 5 people get off and 10 (twice as many as at 1st stop) people get on. On the 3rd stop, 10 people get off. So there are (5 5 + 10 10) 0 passengers left, which leaves the bus driver as the only person on board the bus. Did you answer this riddle correctly?
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On the 1st stop, 5 people get on. On the 2nd stop, 5 people get off and 10 (twice as many as at 1st stop) people get on. On the 3rd stop, 10 people get off. So there are (5 5 + 10 10) 0 passengers left, which leaves the bus driver as the only person on board the bus. Did you answer this riddle correctly?
YES NO
From Block To Block Riddle
I carry lots of people.
I pick them up and drop them off.
I might travel from city to city.
I might only go from block to block.
I am a...
I pick them up and drop them off.
I might travel from city to city.
I might only go from block to block.
I am a...
Hint:
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