A beggar on the street can make one cigarette out of every 6 cigarette butts he finds. After one whole day of searching and checking public ashtrays the beggar finds a total of 72 cigarette butts. How many cigarettes can he make and smoke from the butts he found?
What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?