If A, B and C together can finish a piece of work in 4 days. A alone in 12 days and B in 18 days, then C alone can do it in?
Choose the correct choice:
A) 7 days B) 3 days C) 9 days D) 8 days E) 2 days
9 days   9 days   9 days = 1/4 - 1/12 – 1/18 = 1/9 =&gt; 9 days
<result>C</result>
If A, B and C together can finish a piece of work in 4 days. A alone in 12 days and B in 18 days, then C alone can do it in?