a tap can fill a tank in 16 hours . after half the tank is filled , 3 more similar taps are opened . what is the total time taken to fill the tank completely ?  Choose the correct choice from the following options.
A) 2 hrs
B) 1 hrs
C) 10 hrs
D) 5 hrs
E) 4 hrs

Rationale: explanation : a tap can fill a tank in 16 hours . therefore the tap can fill half the tank in 8 hours . one tap take time to fill half of the tank = 8 hrs 4 taps take time to fill half of the tank = 8 / 4 hrs = 2 hrs total time taken to fill the tank = 8 hr + 2 hr = 10 hrs answer : c
Answer: C