Question

Two are used to fill the swimming pool.Pipe A alone fill the tank in 4 hours and pipe B fill the tank in 4 hours.If both pipe s together filled A can turned on and B is turned on 30 minutes later find the take n by each pipe to fill the tank

Answer 1

The pipe A will fill the pool in 2.25 hours and the pipe B will fill the pool in 1.75 hours.

Step-by-step explanation:

Pipe A alone can fill the pool in 4 hours.

So, in 1 hour it fills
`(1)/(4)` part of the pool.

and in 30 minutea it fills
`(1)/(8)` part of the pool.

If the pipe B is opened after 30 minutes the pipe A opened.

So,
`(1-(1)/(8) ) =(7)/(8)` part of the pool is filled by both the pipe.

Again, pipe B alone fills the pool in 4 hours.

Hence, if both the pipes are open then they will fill in one hour
`((1)/(4) +(1)/(4)) =(1)/(2)` part of the pool.

So, the remaining
`(7)/(8)` part of the pool will be filled by both the pipe in
`((7)/(8) )/((1)/(2) ) =(7)/(4)` hours i.e. 1.75 hours.

Therefore pipe A will fill the pool in (0.5 + 1.75) =2.25 hours and pipe B will fill the pool in 1.75 hours. (Answer)