V = ⅓π(3)²(8)
Look at this cone with radius three centimeters and height eight centimeters. Let's find its volume.
A cone fits inside a cylinder of the same radius and height. It takes exactly three cones to fill that cylinder.
The cylinder's volume is pi times radius squared times height.
So a cone is just one-third of that: V equals one-third pi r squared h.
Plug in our numbers. The radius is three, so r squared is nine.
The height is eight.
Multiply nine by eight to get seventy-two.
Now take one-third of seventy-two, which is twenty-four.
That leaves twenty-four pi cubic centimeters.
Using pi about three point one four, that's roughly seventy-five point four cubic centimeters.
The cone holds about seventy-five cubic centimeters of ice cream. Nice scoop!
Now you try. Count the flat faces of this cone. Count the flat faces.