Riddle #835

logic

Past the Bridge Guard

A guard is stationed at the entrance to a bridge. He is tasked to shoot anyone who tries to cross to the other side of the bridge, and to turn away anyone who comes in from the opposite side of the bridge. You are on his side of the bridge and want to escape to the other side. Because the bridge is old and rickety, anyone who tries to cross it does so at a constant speed, and it always takes exactly 10 minutes to cross. The guard comes out of his post every 6 minutes and looks down the bridge for any people trying to leave, and at all other times he sits in his post and snoozes. You know you can sneak past him when he's sleeping, but the problem is that you won't be able to make it all the way to the other side of the bridge before he sees you (since he comes out every 6 minutes, but it takes 10 minutes to cross). One day a brilliant idea comes to you, and soon you've successfully crossed to the other side of the bridge without being shot. How did you do it?
Right after the guard goes back to his post after checking the bridge, you sneak by and make your way down the bridge. After a little bit less than 6 minutes, you turn around and start walking back toward the guard. He will come out and see you, and assume that you are a visitor coming from the other side of the bridge, since you're only about 4 minutes from the end of the other side of the bridge. He will go back into his post since he doesn't plan to turn you away until you reach him, and then you turn back around and make your way the rest of the way to the other side of the bridge.
94.11 %
43 votes

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logic

King's riddle

Allan, Bertrand, and Cecil were caught stealing so the king sent them to the dungeon. But the king decided to give them a chance. He mad them stand in a line and put hats on their heads. He told them that if they answer a riddle, they could go free. Here is the riddle: "Each of you has a hat on your head. You do not know the color of the hat on your own head. If one of you can guess the color of the hat on your head, I will let you free. But before you answer you must keep standing in this line. You cannot turn around. Here are my only hints: there are only black and white hats. At least one hat is black. At least one hat is white." Allan couldn't see any hats. Bertrand could see Allan's hat but not his own. Cecil could see Bertrand's hat and Allan's hat, but not his own. After a minute nobody had solved the riddle. But then a short while later, one of them solved the riddle. Who was is and how did he know?
Bertrand knew the answer because Cecil didn't say anything after one minute. If Bertrand and Allan's hats were both the same color, then Cecil would know what color his hat was. But Cecil didn't know. So Bertrand knew that Allan's hat was a different color than his. Since Allan's hat was black, Betrand knew his hat was white.
87.14 %
55 votes

logic

Clever daughter

Many years ago a wealthy old man was near death. He wished to leave his fortune to one of his three children. The old man wanted to know that his fortune would be in wise hands. He stipulated that his estate would be left to the child who would sing him half as many songs as days that he had left to live.The eldest son said he couldn't comply because he didn't know how many days his father had left to live and besides he was too busy. The youngest son said the same thing. The man ended up leaving his money to his third child a daughter. What did his daughter do?
Every other day, the daughter sang her father a song.
93.70 %
40 votes

logicshort

Missing letter

What's the missing letter? J ? M A M J J A S O N D
F. Eplanation: The letters are the first letter of each of the twelve months. The second month is February.
93.70 %
40 votes

logic

Grandma and Cake

You are on your way to visit your Grandma, who lives at the end of the valley. It's her anniversary, and you want to give her the cakes you've made. Between your house and her house, you have to cross 5 bridges, and as it goes in the land of make believe, there is a troll under every bridge! Each troll, quite rightly, insists that you pay a troll toll. Before you can cross their bridge, you have to give them half of the cakes you are carrying, but as they are kind trolls, they each give you back a single cake. How many cakes do you have to leave home with to make sure that you arrive at Grandma's with exactly 2 cakes?
2 Cakes How? At each bridge you are required to give half of your cakes, and you receive one back. Which leaves you with 2 cakes after every bridge.
93.70 %
40 votes

logic

Night watchman

Once there was a night watchman who had been caught several times sleeping on the job. The boss issued the final warning. On the next night he was caught with his head on his hand and his elbows on the desk. "Aha, I've caught you again," exclaimed the boss. The watchman's eyes popped open immediately and he knew what had happened. Being a quick thinking man, he said one word before looking up at the boss. The boss apologized profusely and went home. What was the one word?
The one word was "AMEN", thus making the Boss believe he was praying rather than sleeping.
93.22 %
37 votes

cleanfunnylogic

Question's wallet

After recent events, Question Mark is annoyed with his brother, Skid Mark. Skid thought it would be funny to hide Question's wallet. He told Question that he would get it back if he finds it. So, first off, Skid laid five colored keys in a row. One of them is a key to a room where Skid is hiding Question's wallet. Using the clues, can you determine the order of the keys and which is the right key? Red: This key is somewhere to the left of the key to the door. Blue: This key is not at one of the ends. Green: This key is three spaces away from the key to the door (2 between). Yellow: This key is next to the key to the door. Orange: This key is in the middle.
The order (from left to right) is Green, Red,Orange, Blue, Yellow. The blue key is the key to the door.
91.22 %
48 votes

cleanfunnylogic

Blind in a hardware store

A blind man walks into a hardware store to buy a hammer. There are hammers hanging behind the front desk, but obviously the blind man isn't able to see them. And yet a few minutes later, he happily walks out of the store, having just purchased a new hammer. How did he do it?
He walks up the the front desk where the clerk is working and says "I'd like to buy a hammer."
93.70 %
40 votes

logic

The manager

Mad Ade's Uncle, Phil Space, who doesn't like what passes for art these days, ran into the National Gallery and caused millions of pounds of damage to several masterpieces. Later that day, Uncle Phil was invited to meet the manager and was warmly thanked for his actions. How come?
Uncle Phil is a fireman The water from his house damaged the paintings as he put out a fire in the Gallery, but in the process rescuing hundreds of millions of pounds worth.
93.84 %
41 votes

logicmath

New York Hair

You are visiting NYC when a man approaches you. "Not counting bald people, I bet a hundred bucks that there are two people living in New York City with the same number of hairs on their heads," he tells you. "I'll take that bet!" you say. You talk to the man for a minute, after which you realize you have lost the bet. What did the man say to prove his case?
This is a classic example of the pigeonhole principle. The argument goes as follows: assume that every non-bald person in New York City has a different number of hairs on their head. Since there are about 9 million people living in NYC, let's say 8 million of them aren't bald. So 8 million people need to have different numbers of hairs on their head. But on average, people only have about 100,000 hairs. So even if there was someone with 1 hair, someone with 2 hairs, someone with 3 hairs, and so on, all the way up to someone with 100,000 hairs, there are still 7,900,000 other people who all need different numbers of hairs on their heads, and furthermore, who all need MORE than 100,000 hairs on their head. You can see that additionally, at least one person would need to have at least 8,000,000 hairs on their head, because there's no way to have 8,000,000 people all have different numbers of hairs between 1 and 7,999,999. But someone having 8,000,000 is an essential impossibility (as is even having 1,000,000 hairs), So there's no way this situation could be the case, where everyone has a different number of hairs. Which means that at least two people have the same number of hairs.
90.86 %
46 votes

cleanEinstein’slogic

Five houses

There is a row of five different color houses. Each house is occupied by a man of different nationality. Each man has a different pet, prefers a different drink, and smokes different brand of cigarettes. The Brit lives in the Red house. The Swede keeps dogs as pets. The Dane drinks tea. The Green house is next to the White house, on the left. The owner of the Green house drinks coffee. The person who smokes Pall Mall rears birds. The owner of the Yellow house smokes Dunhill. The man living in the centre house drinks milk. The Norwegian lives in the first house. The man who smokes Blends lives next to the one who keeps cats. The man who keeps horses lives next to the man who smokes Dunhill. The man who smokes Blue Master drinks beer. The German smokes Prince. The Norwegian lives next to the Blue house. The man who smokes Blends has a neighbour who drinks water. Who has fish at home?
German.
83.96 %
52 votes