Final answer:
A 9-inch round cake pan has a volume that can be calculated using the formula for the volume of a cylinder. Alternative pans that could be used include multiple smaller round cake pans.
Step-by-step explanation:
When a recipe calls for a 9-inch round cake pan, it is referring to the diameter of the pan. To find the volume of a round cake pan, we can use the formula for the volume of a cylinder: V = πr^2h, where r is the radius of the pan and h is the height of the pan. The formula for the volume of a round cake pan can be represented as V = π(4.5)^2h, where 4.5 inches is the radius of a 9-inch round cake pan. To find the volume, we need to know the height of the pan as well.
As for alternative pans that could be used, you could use multiple smaller round cake pans that have a combined volume equal to the volume of the 9-inch round cake pan. For example, you could use two 6-inch round cake pans or three 5-inch round cake pans.