Riddle #783

logic

Measuring Gallons of Water

You have two jugs, one that holds exactly 3 gallons, and one that holds exactly 5 gallons. Using just these two jugs and a fire hose, how can you measure out exactly 4 gallons of water?
Fill the 5-gallon jug to the top, and then pour it into the 3-gallon jug until the 3-gallon jug is full. You now have 2 gallons remaining in the 5-gallon jug. Pour out the 3-gallon jug, and then pour the 2 gallons from the 5-gallon jug into the 3-gallon jug. Finally, fill the 5-gallon jug to the top and pour it into the 3-gallon jug until it's full. Since there was only space left for 1 more gallon in the 3-gallon jug, you now have exactly 4 gallons in the 5-gallon jug.
93.39 %
38 votes

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Mr. Black, Mr. Gray, and Mr. White

Mr. Black, Mr. Gray, and Mr. White are fighting in a truel. They each get a gun and take turns shooting at each other until only one person is left. Mr. Black, who hits his shot 1/3 of the time, gets to shoot first. Mr. Gray, who hits his shot 2/3 of the time, gets to shoot next, assuming he is still alive. Mr. White, who hits his shot all the time, shoots next, assuming he is also alive. The cycle repeats. All three competitors know one another's shooting odds. If you are Mr. Black, where should you shoot first for the highest chance of survival?
He should shoot at the ground. If Mr. Black shoots the ground, it is Mr. Gray's turn. Mr. Gray would rather shoot at Mr. White than Mr. Black, because he is better. If Mr. Gray kills Mr. White, it is just Mr. Black and Mr. Gray left, giving Mr. Black a fair chance of winning. If Mr. Gray does not kill Mr. White, it is Mr. White's turn. He would rather shoot at Mr. Gray and will definitely kill him. Even though it is now Mr. Black against Mr. White, Mr. Black has a better chance of winning than before.
93.70 %
40 votes

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Three daughters

Sam has got three daughters. The eldest daughter is the most honest girl in the universe and she always speaks truth. The middle daughter is a modest woman. She speaks truth and lies according to the situations. The youngest one never speaks truth. Not a single word she spoke was true and would never be true. Sam brought a marriage proposal for one of his girls. It was John. John wanted to marry either the eldest or the youngest daughter of Sam as he can easily identify whether the girl speaks truth or lie! John told his desire to Sam. However, Sam laid a condition. He told John that he will not say who the eldest, middle or youngest one is. Also, he allowed john to ask only one question to identify the eldest or youngest so he can marry one. John asked one question and found the right girl. What was the question and whom should he pick? He asks this question to one of the daughters. If he asked this question to older daughter pointing at other two, he probably would know the youngest one! NO matter, she always speaks truth. If he asked the question to middle one, probably he can choose either. If he asked the youngest one, she always lies and he can find eldest one! No matter, he has to choose the youngest one based on the answer.
The question he asked is, ‘Is she older than her!’ He asks this question to one of the daughters. If he asked this question to older daughter pointing at other two, he probably would know the youngest one! NO matter, she always speaks truth. If he asked the question to middle one, probably he can choose either. If he asked the youngest one, she always lies and he can find eldest one. No matter, he has to choose the youngest one based on the answer.
93.39 %
38 votes

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It will follow you

If will follow you for 1000 miles but not miss home. It desires neither food nor flowers. It fears not water, fire, knives, nor soldiers. But it disappears when the sun sets behind the western mountains. Who Am I?
Shadow.
90.67 %
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Gambling house

Even though the odds are always in favor of the gambling house, why does the establishment insist on a house limit on stakes?
Every casino in the world would go bankrupt without a house limit on stakes. Without it, gamblers would keep doubling their stakes until they won. No matter how bad a losing streak they were on, they would eventually win.
93.05 %
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To sentries

Two sentries were on duty outside a barracks. One faced up the road to watch for anyone approaching from the North. The other looked down the road to see if anyone was approached from the South. Suddenly one of them said to the other, "Why are you smiling?" How did he know that his companion was smiling?
Although the guards were looking in opposite directions, they were not back to back. They were facing each other.
89.58 %
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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).
86.32 %
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Three people in a hotel

Three people check into a hotel. They pay $30 to the manager and go to their room. The manager finds out that the room rate is $25 and gives $5 to the bellboy to return. On the way to the room, the bellboy reasons that $5 would be difficult to share among three people, so he pockets $2 and gives $1 to each person. Now, each person paid $10 and got back $1. So they paid $9 each, totalling $27. The bellboy has $2, totalling $29. ) Where is the remaining dollar?
Each person paid $9, totalling $27. The manager has $25 and the bellboy has $2. The bellboy's $2 should be added to the manager's $25 or substracted from the tenant's $27, not added to the tenants' $27.
93.98 %
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Fancy restaurant

A fancy restaurant in New York was offering a promotional deal. A married couple could eat at the restaurant for half-price on their anniversary. To prevent scams, the couple would need proof of their wedding date. One Thursday evening, a couple claimed it was their anniversary, but didn't bring any proof. The restaurant manager was called to speak with the couple. When the manager asked to hear about the wedding day, the wife replied with the following: "Oh, it was a wonderful Sunday afternoon, birds were chirping, and flowers were in full bloom." After nearly 10 minutes of ranting, she comes to tell him that today was their 28th wedding anniversary. "How lovely", the manager said, "However, you do not qualify for the discount. Today is not your anniversary, you are a liar". How did the manager know that it wasn't their anniversary?
The calendar repeats itself every 28 years. So, if they were married on a Sunday 28 years ago, the day they were at the restaurant would also have to be a Sunday. Since it was a Thursday, the manager knew they were lying, and abruptly kicked them out of his restaurant.
90.47 %
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Young girl was found murdered

On the first day of the school a young girl was found murdered. Police suspect four male teachers and question them. They were asked what they were doing at 8:00 am. Mr. Walter: I was driving to school and I was late. Mr. Thomas: I was checking English exam papers. Mr. Benjamin: I was reading the newspaper. Mr. Calvin: I was with my wife in my office. The police arrested the killer. How did the police find the murderer?
Mr.Thomas as he cannot be checking exam papers on the first day of school.
80.98 %
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