Two pipes A and B can fill a tank in 15 minutes and 20 minutes respectively. Both the pipes are opened together but after 4 minutes, pipe A is turned off. What is the total time required to fill the tank?
Correct answer D. 14 min. 40 sec.
Correct answer D. 14 min. 40 sec.
Tip: press A, B, C or D to answer, and N for the next question.
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