A murderer is condemned to death. He has to choose among three rooms. The first is full of raging fires, the second is full of assassins with loaded guns, and the third is full of lions that haven't eaten in 3 years. Which room is safest for him?
The third one. Lions that haven’t eaten in three years are dead.
A farmer has seventeen sheep. All but nine of them die. How many sheep does he have left?