Answer: 27:1
Explanation:
We know that the volume of cylinder is given by :-
, where r is radius and h is height of the cylinder.
Also, If two figures are similar then ratio of volume is equal to the cube of any dimension .
The ratio of the volume of Pipe A to the volume of Pipe B is given by :-

Hence, the ratio of the volume of Pipe A to the volume of Pipe B = 27:1