If 9 workers can build a brick wall in 20 days, how many workers will be required to build the exact same wall in 12 days?

Step 1: Understand the relationship

This problem involves an inverse proportion. The number of workers ($W$) and the number of days ($D$) required to complete a task are inversely proportional. This means that if you increase the number of workers, the number of days required to complete the same work decreases, and vice versa. The total work done remains constant.

Step 2: Identify given values

From the problem statement, we are given the initial number of workers ($W_1$) and the initial number of days ($D_1$). We are also given the new number of days ($D_2$) and need to find the new number of workers ($W_2$).

Step 3: Substitute values into the formula

Now, we substitute the known values into the inverse proportion formula. We have 9 workers initially taking 20 days, and we want to find $W_2$ workers who can complete the work in 12 days.

Step 4: Solve for the unknown

First, we multiply 9 by 20 to get 180. Then, to find $W_2$, we divide 180 by 12. This calculation gives us the required number of workers.

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