A tap can fill a tank in 16 minutes and another can empty it in 8 minutes. If the tank is already 1/2 full and both the taps are opened together, will the tank be filled or emptied? How long will it take before the tank is either filled completely or emptied completely as the case may be? .
(A) Emptied; 16 mins
(B) Filled; 8 mins
(C) Emptied; 12 mins
(D) Filled; 12 mins
(E) None of These

• if A and B open together
  since B can empty faster than A so tank will empty not fill.
  the whole tank will empty in 16*8/(16-8)
  =16 min
  since tank is half so it will take only 8 min to empty.
  Ans:E
• 14 years agoHelpfull: Yes(24) No(5)
• (1/16)-(1/8)=-1/16
  (-) indicates empty the tank in 16m
• 14 years agoHelpfull: Yes(7) No(5)
• The tank will be emptied. The answer has to be Emptied;8 mins
  As that is not in the options, Answer is (E) None of These.
• 14 years agoHelpfull: Yes(6) No(1)
• As filling time is more than emptying time the tank will be emptied
  already tank is half filled,so for remaining half to empty time taken is reciprocal of:
  1/8 + 1/4 = 8min.
  but to empty remaining half filled tank 4minutes are required
  so answer is 8+4=12
  ans:Emptied,12 mins
• 14 years agoHelpfull: Yes(2) No(20)
• let us consider tap a is on for 8 min.
  so tank would be filled completely.
  and tap B is also on at the same time.
  so it will empty the tank as it requires 8 min to empty completely.
  therefore, emptied 8 min i.e. (e)
• 13 years agoHelpfull: Yes(2) No(0)