Medium riddles

short

Five fingers

What has five finger but is not alive?
A glove.
91.24 %
28 votes

logicmath

Land of Brainopia

In the land of Brainopia, there are three races of people: Mikkos, who tell the truth all the time, Kikkos, who always tell lies, and Zikkos, who tell alternate false and true statements, in which the order is not known (i.e. true, false, true or false, true, false). When interviewing three Brainopians, a foreigner received the following statements: Person 1: I am a Mikko. Person 2: I am a Kikko. Person 3: a. They are both lying. b. I am a Zikko. Can you help the very confused foreigner determine who is who, assuming each person represents a different race?
Person 1 is a Miko. Person 2 is a Ziko. Person 3 is a Kikko.
90.86 %
46 votes

logicmath

How long was he walking

Every day, Jack arrives at the train station from work at 5 pm. His wife leaves home in her car to meet him there at exactly 5 pm, and drives him home. One day, Jack gets to the station an hour early, and starts walking home, until his wife meets him on the road. They get home 30 minutes earlier than usual. How long was he walking? Distances are unspecified. Speeds are unspecified, but constant. Give a number which represents the answer in minutes.
The best way to think about this problem is to consider it from the perspective of the wife. Her round trip was decreased by 30 minutes, which means each leg of her trip was decreased by 15 minutes. Jack must have been walking for 45 minutes.
90.86 %
46 votes

logic

The Monty Hall Problem

On the game show et´s Make a Deal, Monty Hall shows you three doors. Behind one of the doors is a new car, the other two hide goats. You choose one door, perhaps #1. Now Monty shows you what´s behind door #2 and it´s a goat.He gives you the chance to stay with original pick or select door #3. What do you do?
You should always abandon your original choice in favor of the remaining door (#3). When you make your first choice the chance of winning is 1 in 3 or 33%. When you switch doors, you turn a 2 in 3 chance of losing in the first round into a 2 in 3 chance of winning in the second round.
90.67 %
45 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.
90.67 %
45 votes

logicshort

Workers strike

This is a newspaper headline: Workers Strike - Want to Make Less Money! What is going on?
The workers work at the mint and are tired of being overworked. They want to work less, which is making less money, since money is made at the mind!
90.67 %
45 votes

logic

The best archer ever

A duke was hunting in the forest with his men-at-arms and servants when he came across a tree. Upon it, archery targets were painted and smack in the middle of each was an arrow. "Who is this incredibly fine archer?" cried the duke. "I must find him!" After continuing through the forest for a few miles he came across a small boy carrying a bow and arrow. Eventually the boy admitted that it was he who shot the arrows plumb in the center of all the targets. "You didn't just walk up to the targets and hammer the arrows into the middle, did you?" asked the duke worriedly. "No my lord. I shot them from a hundred paces. I swear it by all that I hold holy." "That is truly astonishing," said the duke. "I hereby admit you into my service." The boy thanked him profusely. "But I must ask one favor in return," the duke continued. "You must tell me how you came to be such an outstanding shot." How'd he get to be such a good shot?
The boy shot the arrow, then painted the circle around it.
90.47 %
44 votes

logic

The Devil Game

You die and the devil says he'll let you go to heaven if you beat him in a game. The devil sits you down at a perfectly round table. He gives himself and you an infinite pile of quarters. He says, "OK, we'll take turns putting one quarter down, no overlapping allowed, and the quarters must rest flat on the table surface. The first guy who can't put a quarter down loses." You guys are about to start playing, and the devil says that he'll go first. However, at this point you immediately interject, and ask if you can go first instead. You make this interjection because you are very smart and can place quarters perfectly, and you know that if you go first, you can guarantee victory. Explain how you can guarantee victory.
You place a quarter right in the center of the table. After that, whenever the devil places a quarter on the table, mimic his placement on the opposite side of the table.. If he has a place to place a quarter, so will you. The devil will run out of places to put a quarter before you do.
90.47 %
44 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.
90.47 %
44 votes

logic

Prisoner sentenced to death

You are a prisoner sentenced to death. The Emperor offers you a chance to live by playing a simple game. He gives you 50 black marbles, 50 white marbles and 2 empty bowls. He then says, "Divide these 100 marbles into these 2 bowls. You can divide them any way you like as long as you use all the marbles. Then I will blindfold you and mix the bowls around. You then can choose one bowl and remove ONE marble. If the marble is WHITE you will live, but if the marble is BLACK... you will die." How do you divide the marbles up so that you have the greatest probability of choosing a WHITE marble? HINT: The answer does not guarantee 100% you will chose a white marble, but you have a much better chance.
Place 1 white marble in the bowl, and place the rest of the marbles in the other bowl (49 whites, and 50 blacks). This way you begin a 50/50 chance of choosing the bowl with just one white marble, therefore life! BUT even if you choose the other bowl, you still have almost a 50/50 chance at picking one of the 49 white marbles.
90.47 %
44 votes