A pipe of diameter ‘d’ can drain a certain water tank in 40 minutes. The time taken by a pipe of diameter ‘2d’ for doing the same job is :
The time of flow of water through the pipes is inversely proportional to the area of the pipes.
The ratio of area of the two pipes are
=$$\frac{\pi \times (2D)^{2}}{\pi \times (D)^{2}}$$=4:1
Thus, the time taken by the larger pipe will be one-fourth of the smaller pipe.
Hence, the time taken by the larger pipe is =40/4=10.
Create a FREE account and get: