Question

spot
the stream
Two pipes together can fill a tank in 12 hours. W the first pipe can
the tank 10 hours faster than the second then how many hours will the
second pipe take to fill the tank?
ater taps together fil​

Answer 1

Explanation:

Two pipes together can fill a tank in 12 hours. Hence x is 30 hours

Answer 2

Explanation:

Let two pipes A and B are such that pipe takes x hours to fill the tank if working alone.

Then time taken by pipe A will be =x–5

So work done by pipe B in one hour =1x

And work done by pipe A in one hour =1x–5

Therefore work done by A and B together =1x–5+1x

Also A and B take 6 hours to fill the tank when working together.

So work done by A and B together will also be =16

A.T.Q.

1x–5+1x=16

Or x–5+xx(x–5)=16

Or 2x–5x2–5x=16

Multiplying both sides by 6(x2–5 x ) we get

6(2x–5)=1(x2–5x)

Or 12x–30=x2–5x

Or x2–17x+30=0

Or x2–15x–2x+30=0

Or x(x–15)–2(x–15)=0

Or (x–15)(x–2)=0

⇒ either x=15 or x=2

But x=2 is rejected as slower pipe takes more than 5 hours to fill the tank.

Thus slower pipe takes 15 hours and faster pipe takes 15–5=10 hours to fill the tank.