Logic riddles

logicmath

5 Pirates Fight for 100 Gold

There are 5 pirates in a ship. Pirates have hierarchy C1, C2, C3, C4 and C5.C1 designation is the highest and C5 is the lowest. These pirates have three characteristics : a. Every pirate is so greedy that he can even take lives to make more money. b. Every pirate desperately wants to stay alive. c. They are all very intelligent.There are total 100 gold coins on the ship. The person with the highest designation on the deck is expected to make the distribution. If the majority on the deck does not agree to the distribution proposed, the highest designation pirate will be thrown out of the ship (or simply killed). The first priority of the pirates is to stay alive and second to maximize the gold they get. Pirate 5 devises a plan which he knows will be accepted for sure and will maximize his gold. What is his plan?
To understand the answer,we need to reduce this problem to only 2 pirates. So what happens if there are only 2 pirates. Pirate 2 can easily propose that he gets all the 100 gold coins. Since he constitutes 50% of the pirates, the proposal has to be accepted leaving Pirate 1 with nothing. Now let’s look at 3 pirates situation, Pirate 3 knows that if his proposal does not get accepted, then pirate 2 will get all the gold and pirate 1 will get nothing. So he decides to bribe pirate 1 with one gold coin. Pirate 1 knows that one gold coin is better than nothing so he has to back pirate 3. Pirate 3 proposes {pirate 1, pirate 2, pirate 3} {1, 0, 99}. Since pirate 1 and 3 will vote for it, it will be accepted. If there are 4 pirates, pirate 4 needs to get one more pirate to vote for his proposal. Pirate 4 realizes that if he dies, pirate 2 will get nothing (according to the proposal with 3 pirates) so he can easily bribe pirate 2 with one gold coin to get his vote. So the distribution will be {0, 1, 0, 99}. Smart right? Now can you figure out the distribution with 5 pirates? Let’s see. Pirate 5 needs 2 votes and he knows that if he dies, pirate 1 and 3 will get nothing. He can easily bribe pirates 1 and 3 with one gold coin each to get their vote. In the end, he proposes {1, 0, 1, 0, 98}. This proposal will get accepted and provide the maximum amount of gold to pirate 5.
91.22 %
48 votes

logicmystery

The girlfriend

It was a man's birthday. He lay dead in the lounge room of his house. Next to his body was a note, written in pencil. The note read 'Happy Birthday, Friend'. The victim had a girlfriend and the police suspected her ex-boyfriend. They could find no obvious evidence. While searching the ex-boyfriend's car, the police saw an envelope with the girlfriend's address written on it. They thought they would get the handwriting checked against the note. The scientist in charge came in early to work the next day; it was 7am. He looked out his window which faced east and stared at the rising sun and it was then that he realised how to prove the ex-boyfriend killed the man, even though the girlfriend's address was not written in the same handwriting. How did he do it?
The scientist's office faced east, and the sun was coming in through the window at a very low angle. He saw some very faint shadows on the surface of the envelope. He looked closer. There were the words embossed on the paper. They read "Happy Birthday, Friend". The ex-boyfriend had forgotten that a pencil leaves an impression on paper beneath the page written on.
86.32 %
41 votes

logicshort

Akbar and Birbal

One day, Emperor Akbar posed a question to Birbal. He asked him what Birbal would choose if he offered either justice or a gold coin. "The gold coin," said Birbal without hesitation. On hearing this, Akbar was taken aback. "You would prefer a gold coin to justice?" he asked, not believing his own ears. "Yes," said Birbal. The other courtiers were amazed by Birbal's display of idiocy. They were full of glee that Birbal had finally managed himself to do what these courtiers had not been able to do for a long time - discredit Birbal in the emperor's eyes! "I would have been disappointed if this was the choice made even by my lowliest of servants," continued the emperor. "But coming from you it's not only disappointing, but shocking and sad. I did not know you were so debased!" How did Birbal justify his answer to the enraged and hurt Emperor?
"One asks for what one does not have, Your Majesty." said Birbal, smiling gently and in quiet tones. "Under Your Majesty´s rule, justice is available to everybody. But I am a spendthrift and always short of money and therefore I said I would choose the gold coin." The answer immensely pleased the emperor and respect for Birbal was once again restored in the emperor's eyes.
93.39 %
38 votes

logicshort

The rarest book in the World

A man had a book that was worth $40,000. There were only 2 books in existence. He threw it in the furnace, reducing it to a pile of soot. Why did he do this?
He destroyed the book because he has two, and by only having one, the value goes up.
93.39 %
38 votes

animallogicmath

Chickens and Rabbits

There are several chickens and rabbits in a cage (with no other types of animals). There are 72 heads and 200 feet inside the cage. How many chickens are there, and how many rabbits?
Let c be the number of chickens, and r be the number of rabbits. r + c = 72 4r + 2c = 200 To solve the equations, we multiply the first by two, then subtract the second. 2r + 2c = 144 2r = 56 r = 28 c = 44 So there are 44 chickens and 28 rabbits in the cage.
93.39 %
38 votes

logicmath

The Witch

A witch owns a field containing many gold mines. She hires one man at a time to mine this gold for her. She promises 10% of what a man mines in a day, and he gives her the rest. Because she is blind, she has three magic bags who can talk. They report how much gold they held each day, and this is how she finds out if men are cheating her. Upon getting the job, each man agrees that if he isn't honest, then he will be turned into stone. So around the witch's mines, many statues lay! Now comes an honest man named Garry. He accepts the job gladly. The witch, who didn't trust him said, "If I wrongly accuse you of cheating me, then I'll be turned into stone." That night, Garry, having honestly done his first day's job, overheard the bags talking to the witch. He then formulated a plan... The next night, he submitted his gold, and kept 1.6 pounds of gold. Later, the witch talked with her bags. The first bag said it held 16 pounds that day. The second one said it held 5 pounds. The third one said it held 2 pounds. Beaming, the witch confronted Garry. "You scoundrel, you think you could fool me. Now you shall turn into stone!" the witch cried. One second later, the witch was hard as a rock, and very grey-looking. How did Garry brilliantly deceive the witch?
Garry put 2 lbs. in bag #1. 3 lbs. were put in bag #2. 11 lb. were put into bag #3. He then put bag #2 into bag #3, and bag #1 into bag #2. The bags only felt the weight of the gold above it. Thus they inadvertently gave the message that 23 lbs. were taken.
91.04 %
47 votes

logic

Catholic school

A young boy went to a Catholic school. During school he started goofing around, so the teacher called him out and sent him to the Pastor. Since this was a traditional school the boy would be spanked, but the Pastor believed in giving people a chance. He said, "If you can ask me a question about something you learned and I don't know the answer on the spot you will go free." The boy may have been lazy, but he was very witty. He asked, "What is it that you can see and I can see, usually every day, but God cannot see." The Pastor stood there, stumped. He couldn't figure it out because he strongly believed that God sees and knows all, and that there is only one God. The boy smiled and told him. What was it?
His own equal! We see our equals everyday, but since there is one God, he cannot see someone equal to himself.
93.55 %
39 votes

logic

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

logic

Hidden message

Find a short hidden message in the list of words below. carrot fiasco nephew spring rabbit sonata tailor bureau legacy corona travel bikini object happen soften picnic option waited effigy adverb report accuse animal shriek esteem oyster
Starting with the first two words, take the first and last letters, reading from left to right. Example: Carrot fiascO "from these pairs" the message is as follows: CONGRATULATIONS CODE BREAKER
91.04 %
47 votes

logicshortwhat am I

Present in sun, but not in rain

Only one color, but not one size. Stuck at the bottom, yet I easily fly. Present in sun, but not in rain. Doing no harm, and feeling no pain. What Am I?
Shadow.
91.04 %
47 votes