Alex and Felicia each have cats as pets. Alex buys cat food in cylindrical cans that are 6cm in diameter and 12cm high. Felicia buys cat food in cylindrical cans that are 12cm in diameter and 6cm high. What is the ratio of the volume one of Alex's cans to the volume of Felicia's cans?
2019 AMC 8 Question 9
For this problem, any cylindrical can has two circular bases and a height. The volume of such a cylinder is$$\pi \times r^2\times h,$$where $r$ is the radius of the circular base and $h$ is the height.
This should allow you to find the volume of each can of cat food. Caution: The diameter is not the radius!