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:
[tex]V=\pi r^2 h[/tex]
Therefore, the volume of the 1st cylinder is
[tex]V=\pi r^2 9=9\pi r^2[/tex]
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
[tex]V'=\pi r'^2 h = \pi (2r)^2 9 =9\pi (4r^2)=36\pi r^2[/tex]
This means that the number of pitchers that can be filled by this 2nd cylinder is
[tex]n=\frac{V'}{V}=\frac{36\pi r^2}{9\pi r^2}=4[/tex]