Riddle #810

logic

Two tape recorders

Marty and Jill want to copy three 60 minute tapes. They have two tape recorders that will dub the tapes for them, so they can do two at a time. It takes 30 minutes for each side to complete; therefore in one hour two tapes will be done, and in another hour the third will be done. Jill says all three tapes can be made in 90 minutes. How?
Jill will rotate the three tapes. Let's call them tapes 1,2, and 3 with sides A and B. In the first 30 minutes they will tape 1A and 2A, in the second 3 minutes they will tape 1B and 3A (Tape 1 is now done). Finally, in the last 30 minutes, they will tape 2B and 3B.
93.22 %
37 votes

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logic

German/Swiss border

A woman who lived in Germany during World War II wanted to cross the German/Swiss border in order to escape Nazi pursuers. The bridge which she is to cross is a half mile across, over a large canyon. Every three minutes a guard comes out of his bunker and checks if anyone is on the bridge. If a person is caught trying to escape German side to the Swiss side they are shot. If caught crossing the other direction without papers they are sent back. She knows that it takes at least five minutes to cross the bridge, in which time the guard will see her crossing and shoot her. How does she get across?
She waits until the guard goes inside his hunt, and begins to walk across the bridge. She gets a little more than half way, turns around, and begins to walk toward the geman side once more. The guard comes out, sees that she has no papers, and sends her "back" to the swiss side.
91.71 %
51 votes

cleanEinstein’slogic

Ships in a port

There are 5 ships in a port. The Greek ship leaves at six and carries coffee. The ship in the middle has a black chimney. The English ship leaves at nine. The French ship with a blue chimney is to the left of a ship that carries coffee. To the right of the ship carrying cocoa is a ship going to Marseille. The Brazilian ship is heading for Manila. Next to the ship carrying rice is a ship with a green chimney. A ship going to Genoa leaves at five. The Spanish ship leaves at seven and is to the right of the ship going to Marseille. The ship with a red chimney goes to Hamburg. Next to the ship leaving at seven is a ship with a white chimney. The ship on the border carries corn. The ship with a black chimney leaves at eight. The ship carrying corn is anchored next to the ship carrying rice. The ship to Hamburg leaves at six. Which ship goes to Port Said? Which ship carries tea?
The French ship.
91.55 %
50 votes

funnylogicshort

Escape strtegy

Your bike crashed into the dark forest and suddenly you saw and deadly panther and jaguar. You got just one bullet. What is your escape strategy?
Simple, you must shoot the panther and drive off in the jaguar (car).
93.39 %
38 votes

logicmystery

The Smith family

The Smith family is a very wealthy family that lives in a big, circular home. One morning, Mr. Smith woke up and saw a strawberry jam stain on his new carpet. He figured out that everyone who was there that morning had a jam sandwich. By reading the following excuses, figure out who spilled the jam. Billy Smith: "I was outside playing basketball." The Maid: "I was dusting the corners of the house." Chef: "I was starting to make lunch for later." Who is lying?
It was the maid. The house is circular, it has no corners.
94.11 %
43 votes

logic

10 Cigarette butts

Bruce is an inmate at a large prison, and like most of the other prisoners, he smokes cigarettes. During his time in the prison, Bruce finds that if he has 3 cigarette butts, he can cram them together and turn them into 1 full cigarette. Whenever he smokes a cigarette, it turns into a cigarette butt. One day, Bruce is in his cell talking to one of his cellmates, Steve. "I really want to smoke 5 cigarettes today, but all I have are these 10 cigarette butts," Bruce tells Steve. "I'm not sure that will be enough." "Why don't you borrow some of Tom's cigarette butts?" asks Steve, pointing over to a small pile of cigarette butts on the bed of their third cellmate, Tom, who is out for the day on a community service project. "I can't," Bruce says. "Tom always counts exactly how many cigarette butts are in his pile, and he'd probably kill me if he noticed that I had taken any." However, after thinking for a while, Bruce figures out a way that he can smoke 5 cigarettes without angering Tom. What is his plan?
Bruce takes 9 of his 10 cigarette butts and turns them into 3 cigarettes total (remember, 3 cigarette butts can be turned into 1 cigarette). He smokes all three of these, and now he has 4 cigarette butts. He then turns 3 of the 4 cigarette butts into another cigarette and smokes it. He has now smoked 4 cigarettes and has 2 cigarette butts. For the final step, he goes and borrows one of Tom's cigarette butts. With this cigarette butt plus the 2 he already has, he is able to make his 5th cigarette to smoke. After smoking it, he is left with 1 cigarette butt, which he puts back in Tom's pile so that Tom won't find anything missing.
93.39 %
38 votes

logic

Government School Inspector

Last week, the local Primary school was visited by the Government School Inspector who was there to check that teachers were performing well in their respective classes. He was very impressed with one particular teacher. The Inspector noticed that each time the class teacher asked a question, every child in the class put up their hands enthusiastically to answer it. More surprisingly, whilst the teacher chose a different child to answer the questions each time, the answers were always correct. Why would this be?
The children were instructed to ALL raise their hands whenever a question was asked. It did not matter whether they knew the answer or not. If they did not know the answer, however, they would raise their LEFT hand. If they knew the answer, they would raise their RIGHT hand. The class teacher would choose a different child each time, but always the ones who had their RIGHT hand raised.
93.84 %
41 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