If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

A thief is convicted in Mexico. He gets the death penalty. The judge allows him to say the last sentence to determine how the penalty will be carried out. If the thief lies, he will be hanged, if he speaks the truth he will be beheaded. The thief tells the last sentence and to everybody's surprise some minutes later he is set free because the judge cannot determine his penalty. What did the thief say?

A boy was at a carnival and went to a booth where a man said to the boy, "If I write your exact weight on this piece of paper then you have to give me $50, but if I cannot, I will pay you $50." The boy looked around and saw no scale so he agrees, thinking no matter what the carny writes he'll just say he weighs more or less. In the end the boy ended up paying the man $50. How did the man win the bet?

If 21x = 79x, what is the value of x?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

Below is the sum of symbols in each row and column in the figure. Analyzing the figure, can you find out the value of the symbols?

What runs around the whole yard without moving?

A girl was sitting in her hotel room when she heard a knock on the door. She opened the door and found that a man was standing outside.
The man said, "Oh! I am really sorry, I thought this was my room."
He then walked through the corridor to the elevator. The girl did not know the man. She closed her door and called security asking them to apprehend the man.
What made her suspicious of that man? He might have been genuinely mistaken.

Take one out and scratch my head, I am now black but once was red. What am I?