A is twice as good as B and together they can finish the work in 18 days. In how many days A will finish the same work?

Sure, let's solve this step by step:

Step 1: Let's assume the amount of work to be 1 (for simplicity).

Step 2: Let's say B can do the work in 'b' days. So, the work done by B in 1 day would be 1/b.

Step 3: Since A is twice as good as B, A can do the work in 'b/2' days. So, the work done by A in 1 day would be 2/b.

Step 4: According to the problem, A and B together can finish the work in 18 days. So, the work done by A and B together in 1 day would be 1/18.

Step 5: The work done by A and B together in 1 day is the sum of the work done by A in 1 day and the work done by B in 1 day. So, we have the equation: 1/b + 2/b = 1/18.

Step 6: Solving this equation gives us b = 27. This means B can finish the work in 27 days.

Step 7: Since A is twice as good as B, A can finish the work in 'b/2' days. So, A can finish the work in 27/2 = 13.5 days.

So, A will finish the same work in 13.5 days.