Question

A cylindrical container is used to hold drinking water on the sidelines for a football team. The maximum capacity of the container is 26,460 mL. If the height of the container is 60 cm, what is the radius of the cylinder? (1 mL = 1 cm3)
A. 21 cm B. 7.35 cm C. 220.5 cm D. 42 cm

Answer 1

To solve this we are going to use the formula for the volume of a cylinder: $V= \pi r^2h$
where
$V$ is the volume of the cylinder in cube centimeters 
$r$ is the radius of the cylinder in centimeters 
$h$ is the height of the cylinder in centimeters 

We know for the problem that volume of our cylinder is 26,460 mL. Since 1 mL =$1cm^3$, the volume of our cylinder is $26460cm^3$. We also know for our problem that the height of our cylinder is 60 cm, so $h=60$. Lets replace those values in our formula and solve for $r$:
$V= \pi r^2h$
$26460= \pi r^2(60)$
$26460=60 \pi r^2$
$r^2= \frac{26460}{60 \pi }$
$r^2= \frac{441}{ \pi }$
$r= \sqrt{ \frac{441}{ \pi } }$
$r= \frac{21}{ \sqrt{ \pi } }$
$r=11.8$

We can conclude that the radius of the football team's cylindrical container is 11.8 cm