B is twice as good as workman as A and together they finish a piece of work in 18 days. In how many days will B alone finish the work?

🧠 Explanation:

Let A’s 1-day work = 1 unit
Then B’s 1-day work = 2 units
Together 1-day work = 1 + 2 = 3 units
Total work in 18 days = 18 × 3 = 54 units
B alone time = 54 ÷ 2 = 27 days
A alone time = 54 ÷ 1 = 54 days