7 teps of the same size fill a tank in 1 hour 36 minutes.

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

1 h = 60 min

i.e., 1 h 36 min = (60+36) min = 96 min
 

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

So, it is a case of inverse proportion.

Now, $7 \times 96=8 \times x$

$\Rightarrow x=\frac{7 \times 96}{8}$

$\Rightarrow x=84$

Therefore, 8 taps of the same size will take 84 min or 1 h 24 min to fill the tank.