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 women alone in 18 days, how long will a boy take to complete the work?
Choose one.
A) 6days B) 8days C) 9days D) 7days E) 5days
Explanation:   (1 Man + 1 woman + 1 boy)’s 1day’s work = 1/3   1 man’s 1 day work = 1/6   1womans 1 day’s work = 1/18   (1 Man + 1 woman) ‘s 1 day’s work = 1/6 + 1/18 = 2/9   Therefore, 1 boys 1 day’s work = 1/3 – 2/9 = 3-2/9 = 1/9   Therefore, the boy alone can finish the work in 9 days.   Answer: Option 9days
<result>C</result>
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 women alone in 18 days, how long will a boy take to complete the work?