A tap drips at a rate of one drop/second. 600 drops make 100 ml. The number of liters wasted in 300 days is -

$$\eqalign{ & {\text{1 second }} \to {\text{ 1 drop}} \cr & {\text{Number of second in 300 days}} \cr & \left( {{{24}_{{\text{hrs}}}} \times {{60}_{{\text{mins}}}} \times {{60}_{{\text{sec}}}}} \right) \times 300\,{\text{days}} \cr & {\text{Number of milli - liters wasted}} \cr & {\text{100}} \times \frac{{24 \times 60 \times 60 \times 300}}{{600}} \cr & = 43200 \times 100 \cr & = 4320000\,{\text{ml}} \cr & = \frac{{4320000}}{{1000}} \cr & = 4320\,{\text{liters}} \cr} $$