Question

Two pipes can fill a tank in 15 hours and 12 hours respectively and a third pipe can empty it in 4 hours. pipes be opened in order at 8 A.M., 9 A.M. and 11 A.M. respectively, the tank will be emptied at​

Answer 1

$\huge\underline\bold\blue{ANSWER}$

>>Assume the capacity of tank = 60 units

>>Pipe 1 fills 12 unit in 3 hrs ie 4 unit in 1 hr

>>Pipe2 fills 10 units in 2 hrs ie 5 unit in 1 hr

At 11 am tank has 22 unit water

=>After 11 am…

pipe3 empties 15 unit in 1 hr but 9 unit again filled by pipes 1 & 2

=> pipe3 emptying (15–9)= 6 unit/hr rate

Hence, the whole 22 units will be emptied in 22/6 = 11/3 hrs = 3 hrs 40 min . . . . . . . . . . . . Ans

ie at 2:40 pm . . . . . . . . . Ans

>>Justification:

=>At 12 noon tank has (22+9)-15= 16 unit water

=>At 1 pm tank has ( 16+9)-15= 10 unit

=>At 2 pm tank has (10+ 9)-15 = 4 unit

=>At 2:40 pm tank has (4+6) - 10 = 0 unit