A can do a piece of work in 28 days which B can do in 12 days. B worked at it for 9 days. A can finish the remaining work in ? Choose the correct choice from the following options
A) 3 days  B) 5 days  C) 6 days  D) 7 days  E) 11 days
B's 9 day's work = 9 x (1/12) = 3/4   Remaining work = (1 - 3/4) = 1/4   1/4 work is done by A in = 28 x (1/4) = 7 days.   answer : 7 days
<result>D</result>
A can do a piece of work in 28 days which B can do in 12 days. B worked at it for 9 days. A can finish the remaining work in ?