What is the volume of this right cone?

40
300
400
480

We can find the volume of this cone with the formula 

V = (pi)(r^2)(h/3)
We will use 3.14 as it is the most used approxmiation of pi.
In the diagram, the radius is 10 cm.
And the height is 12 cm.

Plug all those values into the formula.

V = (3.14)(10^2)(12/3) ; Our starting equation
V = (3.14)(100)(12/3)   ; 10^2 is equal to 100
V = (314)(12/3)             ; Multiply 100 by 3.14
V = (314)(4)                  ; 12 divided by 3 is 4
V = 1256

The volume of the cone is 1,256 cm3.