Pipe A and pipe B fill water into a tank of capacity 5000 litres, at a rate of 200 l/min and 50 l/min. Pipe C drains at a rate of 25 l/min. Pipe A is open for 1 min and closed, then pipe B is open for 2 min and closed. Further the pipe c is opened and drained for another 2 min. This process is repeated until the tank is filled. How long will it take to fill the tank?  Choose the correct choice from the following answers:
A) 120  B) 100  C) 140  D) 80  E) 90
tank capacity: 5000 L,   1st- 200 l/min for 1 min, volume filled: 200 L   2nd- 100 l/min for 2 min, volume filled: 100 L   3rd (water draining) : 25 l/min*2 : 50 L   total :  (200+100)-50= 
<gadget id="calculator"> (200+100)-50</gadget>
<output>250</output>
250 L filled for 1 cycle   number of 250 in 5000 L tank :1000/250= 20   time taken to fill: 20* total time= 20*5= 
<gadget id="calculator">20*5</gadget>
<output>100</output>
100 (option 100)
<result>B</result>
Pipe A and pipe B fill water into a tank of capacity 5000 litres, at a rate of 200 l/min and 50 l/min. Pipe C drains at a rate of 25 l/min. Pipe A is open for 1 min and closed, then pipe B is open for 2 min and closed. Further the pipe c is opened and drained for another 2 min. This process is repeated until the tank is filled. How long will it take to fill the tank?