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?
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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?
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The Train Of Love
A young man, living in Manhattan, New York, has two girlfriends. One lives to the North, in the Bronx, and the other lives to the South, in Brooklyn.
He likes both girls equally but can only visit one each weekend. He therefore leaves it to chance and takes the first train that arrives when he reaches the train station.
Even though the man arrives at a totally random time every Saturday morning and the Brooklyn and Bronx trains arrive equally often (every ten minutes), he finds himself visiting the girl in Brooklyn on average nine times out of ten. How could the odds so heavily favor taking the Brooklyn train?
He likes both girls equally but can only visit one each weekend. He therefore leaves it to chance and takes the first train that arrives when he reaches the train station.
Even though the man arrives at a totally random time every Saturday morning and the Brooklyn and Bronx trains arrive equally often (every ten minutes), he finds himself visiting the girl in Brooklyn on average nine times out of ten. How could the odds so heavily favor taking the Brooklyn train?
Hint: Think of a way the train schedules might favor one train over the other.
The Brooklyn train leaves exactly 1 minute before the Bronx train.
Let's say the Brooklyn train arrives at 09:00, 09:10, 09:20, etc. and the Bronx train arrives one minute after at 09:01, 09:11, 09:21, etc. Consider the ten minute interval from 09:00 to 09:10. If the man arrives between 09:00 and 09:01, the 09:01 Bronx train will be the first to arrive (assuming that he doesn't arrive at exactly 09:00). If the man arrives between 09:01 and 09:10, the 09:10 Brooklyn train will be the first to arrive. In any ten minute period, the Brooklyn train will be the first to arrive in nine of the ten minutes. Did you answer this riddle correctly?
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Let's say the Brooklyn train arrives at 09:00, 09:10, 09:20, etc. and the Bronx train arrives one minute after at 09:01, 09:11, 09:21, etc. Consider the ten minute interval from 09:00 to 09:10. If the man arrives between 09:00 and 09:01, the 09:01 Bronx train will be the first to arrive (assuming that he doesn't arrive at exactly 09:00). If the man arrives between 09:01 and 09:10, the 09:10 Brooklyn train will be the first to arrive. In any ten minute period, the Brooklyn train will be the first to arrive in nine of the ten minutes. Did you answer this riddle correctly?
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The Train Crash Riddle
There was a train crash. The police said that there were no casualties, but 2 bodies were found. How is this possible?
Hint:
The train fell out of the track and plowed through the soil, opening two hidden graves. Did you answer this riddle correctly?
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The Hijacker Riddle
A man hijacks an airplane transporting both passengers(8 of them) and valuable cargo. After taking the cargo, the man demands nine parachutes, puts one of them on, and jumps, leaving the other eight behind. Why did he want eight?
Hint:
If the officials thought he was jumping with a hostage, they would never risk giving him a faulty parachute. Did you answer this riddle correctly?
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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?
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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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Dark But Not A Room With Curtains
I'm sometimes dark but I'm not a room with curtains
I sometimes contain peanut butter but I'm not a sandwich
I'm sometimes melted but I'm not an ice cube
I'm sometimes in cookies but I'm not a raisin
I'm sometimes a bar but I'm not made of metal
I'm sometimes a chip but I'm not made of potato
What am I?
I sometimes contain peanut butter but I'm not a sandwich
I'm sometimes melted but I'm not an ice cube
I'm sometimes in cookies but I'm not a raisin
I'm sometimes a bar but I'm not made of metal
I'm sometimes a chip but I'm not made of potato
What am I?
Hint:
How Many Chocolates Can You Get?
A shop sells 1 chocolate at $1. You can exchange 3 wrappers for 1 chocolate. If you have $15, how many chocolates can you get?
Hint:
15 chocolates with resale. 15 then with 15 wrappers you get 5 more chocolates. With 3 wrappers from the 5 new chocolates you get 1 more chocolate. And with these 1 more wrapper and the remaining 2 wrappers you get 1 more chocolate. Hence you get total 15 + 5 + 1 + 1 = 22 Did you answer this riddle correctly?
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Burns Fat But Saves You Money
Hint:
Traveling A Great Distance
How do you travel a great distance without letting your feet touch the ground, while never leaving it?
Hint:
Fifty One Bicycles
Hint:
The man was playing a poker game and cheated. The bicycles are a type of card. Did you answer this riddle correctly?
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YES NO
What's Black And White And Red All Over Riddle
Hint:
Almost Hit By A Car Riddle
A man walked home after having been out drinking. He walked down the middle of a deserted country road. There were no streetlights to illuminate the road and there was no moonlight. He was dressed all in black. Suddenly a car that did not have its headlights on came racing down the road. At the last moment, the driver of the car saw the man and swerved to avoid him.
How did he manage to see him?
How did he manage to see him?
Hint:
He was returning home in the middle of the day, so anyone could have seen him. Did you answer this riddle correctly?
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YES NO
Americans In A Pub Riddle
There were two Americans sitting in a British Pub. One of them was the father of the other one's son. How could this be so?
Hint:
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