\(\frac{3}{4}+\left\{\frac{3}{4}+\frac{3}{4}\div\left(\frac{3}{4}+\frac{3}{4}\right)\right\}\)=?
A water tank is \( \frac{2}{5} \)th full. Inlet A can fill the tank in 12 minutes while an outlet pipe B can empty it in 6 minutes. If both the pipes are open, how long will it take to empty or fill the tank completely?
It fills in 4.8 min
It empties in 4.8 min
It fills in 5.6 min
It empties in 5.6 min