A, B and C can do a piece of work in 24, 30 and 40 days respectively. They start the work together but C leaves 4 days before the completion of the work. In how many days is the work done? Choose the correct choice from the following answers:
A) 11 B) 5 C) 70 D) 11 E) 13
x/24 + x/30 + x/40 = 1   x = 11 days   Answer:11
<result>D</result>
A, B and C can do a piece of work in 24, 30 and 40 days respectively. They start the work together but C leaves 4 days before the completion of the work. In how many days is the work done?