# Logic riddles

## Wife in the kitchen

A man entered his house and was about to hang up his coat when he heard his wife shout; "No John! Don’t do it!" There was a shot and he could hear his wife fall down. When he entered the kitchen he saw his wife and the gun lying on the floor. There was a police officer, a doctor, and a lawyer standing next to her. Peter immediately knew that the police officer had shot her. But how did he come to know?
The police officer has a name on his badge.
57.20 %

## Five daughters

Mary’s father has 5 daughters – Nana, Nene, Nini, Nono. What is the fifth daughters name?
If you answered Nunu, you are wrong. It’s Mary!
56.93 %

## Which night

A man puts on a clean shirt every night before bed. On the first nigh he puts on a blue shirt. He than sleeps for 5 hours. Every one hour more he sleeps than the night before he put on a different color shirt the next night according to this scale: blue, black, red, green, white, pink, orange, brown, purple, yellow, grey, neon green, tan, and teal. Every one hour less he sleeps than the last night he put on a different color shirt the next night going backwards on his scale. If he were to wear a blue shirt because he slept more hours than the last night he does. If it was because he slept less hours than the night before he skips it and wears a teal shirt instead. If he goes backwards on the scale and goes to blue but would not wear a blue shirt he still counts blue in his going backwards on his scale. The second night the man wears a blue shirt because he did not sleep any more or less hours than the last night. The man sleeps for six hours that night. The next night he sleeps for five hours. Night number four he sleeps for eight hours. The next night he sleeps for seven hours. The next night he sleeps so well he sleeps for 11 hours. Night number seven he stays up so late he only sleeps for four hours. The next night he is so tired he sleeps for eight hours. The next night he sleeps for eight hours again. Night number ten he sleeps for 14 hours because he is sick. Since he slept so long the last night he only sleeps for seven hours. The next night he is a little bit tired so he sleeps for eight hours. The night after that he had to do so much work he only slept five hours. The next night at work they let him out early and he slept for nine hours. The next night he slept for eight hours. And the last night the man did he slept for ten hours. The next night he put on a different color shirt according to his scale, but the next night he randomly picked a shirt. At what night will the man wear a blue shirt again?
12th Night.
56.40 %

## A liar and a truth teller

You are walking down a path when you come to two doors. Opening one of the doors will lead you to a life of prosperity and happiness, while opening the other door will lead to a life of misery and sorrow. You don't know which door leads to which life. In front of the doors are two twin brothers who know which door leads where. One of the brothers always lies, and the other always tells the truth. You don't know which brother is the liar and which is the truth-teller. You are allowed to ask one single question to one of the brothers (not both) to figure out which door to open. What question should you ask?
Ask "If I asked your brother what the good door is, what would he say?" If you ask the truth-telling brother, he will point to the bad door, because this is what the lying brother would point to. Alternatively, if you ask the lying brother, he will also point to the bad door, because this is NOT what the truth-telling brother would point to. So whichever door is pointed to, you should go through the other one.
53.58 %

## The greatest mystery ever

Paul is 20 years old in 1980, but only 15 years old in 1985. How is this possible?
The years are in B.C., not A.D. as you probably assumed. Based on the system we use to number the years, the years counted down in B.C. (but they weren't counting backwards back then).
52.86 %

## The Wilson family

The Wilson family is a very wealthy family that lives in a big, circular home. One morning, Mr. Wilson 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. Son: "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.
52.11 %

A man eats dinner, goes up to his bedroom, turns off the lights, and goes to sleep. In the morning, he wakes up and looks outside. Horrified at what he sees, he hurls himself out his window to his death. Why does he do this?
The man was a lighthouse operator. He wasn't supposed to turn off his lights. When he wakes up in the morning, he sees a giant ship that has crashed into the land, causing much catastrophe. Unable to go on, he decides to take his own life.
50.11 %

## 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.
48.54 %

## Burning fire

Alexander is stranded on an island covered in forest. One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process. There are cliffs around the island, so he cannot jump off. How can the Alexander survive the fire? (There are no buckets or any other means to put out the fire)
Alexander picks up a piece of wood and lights it from the fire on the west end of the island. He then quickly carries it near the east end of he island and starts a new fire. The wind will cause that fire to burn out the eastern end and he can then shelter in the burnt area. Alexander survives the fire, but dies of starvation, with all the food in the forest burnt.
47.67 %