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 9 days, how long will a woman take to complete the work?	Select:  A) 12 days  B) 15 days  C) 16 days  D) 24 days  E) 18 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 / 9 ( 1 man + 1 boy ) ‘ s 1 day ’ s work = 1 / 6 + 1 / 9 = 5 / 18 therefore , 1 woman ’ s 1 day ’ s work = 1 / 3 – 5 / 18 = 1 / 18 therefore , the woman alone can finish the work in 18 days . answer : option e
Answer: E