Make Cigarette with 4 Butts

A man picks up cigarette butts from the ground and can make a cigarette with 4 butts. If he finds 16 cigarette butts, how many cigarettes can he make?

Answer

5. He makes 4 cigarettes with the 16 butts. After smoking the 4 cigarettes, he will have 4 more butts to make another cigarette.