A can complete a work in 12 days, while B can complete the same work in 18 days. How many days will they take to complete the work together?
Answer: B. 8 days
The combined work rate of A and B is 1/12 + 1/18 = 5/36. Therefore, they will complete the work in 36/5 = 7.2 days, which rounds to 8 days when considering whole days.