8 taps of the same size fill a tank in 27 minutes.
Question:

8 taps of the same size fill a tank in 27 minutes. If two taps go out of order, how long would the remaining taps take to fill the tank?

Solution:

Let x min be the required number of time. Then, we have:

 No. of taps 8 6 Time (in min) 27 xx

Clearly, less number of taps will take more time to fill the tank .

So, it is a case of inverse proportion.

Now, $8 \times 27=6 \times x$

$\Rightarrow x=\frac{8 \times 27}{6}$

$\Rightarrow x=36$

Therefore, it will take 36 min to fill the tank.