A tap can fill a tank in 6 hours. After half the tank is filled, three more similar taps are opened. What is the total time taken to fill the tank completely?
সমাধান
সঠিক উত্তর: Option E
Time taken by one tap to fill half of the tank = 3 hrs.
Part filled by the four taps in 1 hour = 4x 1/6 = 2/3
Remaining Part = 1/2