A man, a woman and a boy can together complete a piece of work in 3 days. If a man alone can do it in 6 days and a boy alone in 12 days, how long will a woman take to complete the work?
Options.
A) 12 days B) 10 days C) 9 days D) 8 days E) 11 days

Rationale: "explanation : ( 1 man + 1 woman + 1 boy ) ’ s 1 day ’ s work = 1 / 3 1 man ’ s 1 day work = 1 / 6 1 boy ’ s 1 day ’ s work = 1 / 1 ( 1 man + 1 boy ) ‘ s 1 day ’ s work = 1 / 6 + 1 / 12 = 1 / 4 therefore , 1 woman ’ s 1 day ’ s work = 1 / 3 – 1 / 4 = 1 / 12 therefore , the woman alone can finish the work in 12 days . answer : option a"
Answer: A