A can finish a piece of work in 4 days. B can do it in 12 days. They work together for two days and then A goes away. In how many days will B finish the work? Choose one.
A) 4 days B) 5 days C) 6 days D) 7 days E) 8 days

Rationale: "2 / 4 + ( 2 + x ) / 12 = 1 = > x = 4 days answer : a"
Answer: A