Answer:
4
Step-by-step explanation:
The 1st cylinder used to fill the pitcher has:
height:
h = 9 in
radius:
r = r
The volume of a cylinder is given by:

Therefore, the volume of the 1st cylinder is

We are told that the water inside this cylinder can fill a certain pitcher, so this is also the volume of the pitcher.
Then, we have a second cylinder, which has height
h = 9 in
and radius
r' = 2r
So the volume of this cylinder is

This means that the number of pitchers that can be filled by this 2nd cylinder is
