The area of a circle is pi*(r squared)
The volume of a cylinder is pi*(r squared)*(perpendicular height)
The volume of a cone is (1/3)* pi*(r squared)*(perpendicular height)
I did it like this because a cone is just a circular pyramid and the volume of any pyramid is 1/3 of its prism partner. (a cylinder is a circular prism)
So radius=2, height=6.5 inch
volume = 1/3 * pi * 2squared * 6.5
volume = 1/3 * pi * 4 * 6.5
volume = 27.23 inches squared. (correct to 2 decimal places)
What nationality are you?
I am Australian and I have never worked in inches before. Don't worry, the maths is the same.
+118677 
