18 men can complete a piece of work in 20 days. In how many days can 12 men complete that piece of work? Choose the correct option
A) 23 days B) 30 days C) 22 days D) 29 days E) 20 days

Rationale: "b 30 days 18 * 20 = 12 * x = > x = 30 days"
Answer: B