Question

4 pipes fill the tank in 1 hour 30 minutes, then to fill the same tank 12 pipes will take time ______.

Answer 1

ANSWER :

1 HOUR 30 MINUTES

EXPLANATION :

Answer

It is given that 4 pipes can fill a tank in 30 minutes. Let 3 pipes fill the tank in x minutes. Clearly more pipes will fill the tank in less time. So it is a case of inverse proportion. If 4pipes can fill the tank in 30 minutes, it takes 4×30 minutes for one pipe to fill the tank. Now 4 is inversely proportional to 30 and the constant of proportionality is k=4×30. Since 3 pipes can fill the tank in x minutes, we must have 3×x=k. Thus we obtain

x= 3

4×30

=120

Hence it takes 98 minutes for 3pipes to fill the tank; i.e., 1 hour 38 minutes.

Answer 2

4 pipes fill the tank in 1 hour 30 minuters thrn to fill the same tank 12 pipes will take time 140