A can finish a work in 12 days and B can do same work in half the time taken by A. then working together, what part of same work they can finish in a day?
Pick one:  A) 1 / 4  B) 1 / 6  C) 1 / 7  D) 1 / 8  E) none of these

Rationale: "explanation : please note in this question , we need to answer part of work for a day rather than complete work . it was worth mentioning here because many do mistake at this point in hurry to solve the question so lets solve now , a ' s 1 day work = 1 / 12 b ' s 1 day work = 1 / 6 [ because b take half the time than a ] ( a + b ) ' s one day work = ( 1 / 12 + 1 / 6 ) = 1 / 4 so in one day 1 / 4 work will be done answer : a"
Answer: A