Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.
"Are you twins," ask the headmaster.
"No," replies the boys.
A man is looking at a photograph of someone. His friend asks who it is. The man replies, “Brothers and sisters, I have none. But that man’s father is my father’s son.†Who was in the photograph?
A man is approaching a broad and barren land. He has a package with him. If somehow, he is unable to open the package before reaching the land, he will die.
A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?
