Question

9. Pipe A can fill a tank in 45 hours and pipe B can empty it in 36 hours. If both the pipes are opened
in the empty tank, in how many hours will it be full?
(a) 9
(b)20
(c) 40 1/2
(d) 81
​

Answer 1

Answer:

Step-by-step explanation:

Work done by A in one hour = 1/45

Work done by B in one hour = -1/13

1/45 - 1/36 = (4–5)/180 = -1/180

The tank will never get filled.

Answer 2

Answer:

it wont ever get full if we dont close the pipe B