Question: a can do a work in 4 hours?
Answer: If A can do the work (W) alone in 4 hours, then he can do 1/4 W per hour, or 1/2 W in 2 hours. ... If B can only do 1/12 of W in one hour, then it will take him 12 hours to complete the work alone. 1.4k views. A and B can do a work in 8 days.