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?
You and a friend are standing in front of two houses. In each house lives a family with two children.
"The family on the left has a boy who loves history, but their other child prefers math," your friend tells you.
"The family on the right has a 7-year old boy, and they just had a new baby," he explains.
"Does either family have a girl?" you ask.
"I'm not sure," your friend says. "But pick the family that you think is more likely to have a girl. If they do have a girl, I'll give you $100."
Which family should you pick, or does it not matter?
You should pick the house on the left. Specifically, there is a 2/3 chance that the family on the left has a girl, whereas there's only a 1/2 chance that the house on the right has a girl.
This is a very counterintuitive riddle. It seems like there should always be a 1/2 chance that a given child is a girl. And in fact there is. The key word there is "given". Because we are not asking about a "given" child for the house on the left. We are asking about what could be either child. Whereas for the house on the right, we are asking about a "given" child...specifically, we're asking about the younger child.
There are 3 possibilities for the children in the first house:
There is no "Girl, Girl" option because we know the house on the left has at least one boy. Since each of these 3 options is equally likely, and 2 of them have one girl, there is a 2/3 chance of there being a girl in the house on the left.
For the house on the right, because we already know the older child is a boy, there are only two possibilities:
And as we can see, there is a 1/2 chance for the house on the right having a girl.
Search for: Boy or Girl paradox
An intelligent trader travels from one place to another with 3 sacks having 30 coconuts each. No sack can hold more than 30 coconuts. On the way, he passes 30 check points. At each check point, he has to give one coconut for every sack he is carrying. What is the maximum number of coconuts that he can have with him at the end of his journey?
He will have 25 coconuts with him at the end. The trick is to reduce the number of sacks as you pass checkpoints. The first 10 checkpoints require 3 coconuts each, which empties his first sack. The next 15 checkpoints require 2 coconuts each, which will empty his second stack. Now, he is left with 1 sack and 5 more checkpoints. So, the 5 checkpoints will take 1 coconut each. Therefore, he will be left with 25 coconuts.
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.
Once upon a time there existed a temple in India which housed three identical idols which spoke to the devotees.
The idols were of – God of Truth, which always spoke the truth; God of Falsehood, which always lied; and God of Diplomacy which sometimes spoke the truth and at other times lied.
The pilgrims come from all parts of the world to get their questions answered by the Gods. But there was a problem. As the idols were indistinguishable, devotees were not sure from which idol to ask their questions and in turn they did not know which God has answered and whether to believe it or not.
Once a wise man visited the temple. He asked the question: "Which God is seated at the centre?" to all the three idols. The idol on the left, centre and right replied God of Truth, God of Diplomacy and God of Falsehood respectively. The wise man at once proclaimed that he had solved the mystery of the temple.
The idols from left to right are: God of Diplomacy, God of Falsehood, God of Truth.
The God of Truth is not seated on the left because he always speaks the truth whereas the idol on the left replied that the God of Truth is seated at the centre.
The God of Truth is also not seated in the centre as he always speaks the truth but the idol at the centre replied that the God of Diplomacy is seated at the centre.
Therefore, the God of Truth is seated on the right. As God of Truth is seated on the right, and he always speaks the truth, then the The God of Falsehood is seated at the centre. The God of Diplomacy is seated on the left and he has lied.
There is a row of five different color houses. Each house is occupied by a man of different nationality. Each man has a different pet, prefers a different drink, and smokes different brand of cigarettes.
The Brit lives in the Red house.
The Swede keeps dogs as pets.
The Dane drinks tea.
The Green house is next to the White house, on the left.
The owner of the Green house drinks coffee.
The person who smokes Pall Mall rears birds.
The owner of the Yellow house smokes Dunhill.
The man living in the centre house drinks milk.
The Norwegian lives in the first house.
The man who smokes Blends lives next to the one who keeps cats.
The man who keeps horses lives next to the man who smokes Dunhill.
The man who smokes Blue Master drinks beer.
The German smokes Prince.
The Norwegian lives next to the Blue house.
The man who smokes Blends has a neighbour who drinks water.
Who has fish at home?
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?