The correct prismoidal formula for volume calculation is :

$$\frac{D}{6}$$ [fitst section area + last section areas + 2 $$\sum$$ even numbered section area + 4 $$\sum$$ odd numbered section area

D [first section area + last section area + $$\sum$$ even numbered section area + 2 $$\sum$$ odd numbered section areas]

$$\frac{D}{3}$$ [fitst section area + last section areas + 4 $$\sum$$ even numbered section area + 2 $$\sum$$ odd numbered section area

$$\frac{D}{3}$$ [fitst section area + last section areas + 2 $$\sum$$ even numbered section area + 4 $$\sum$$ odd numbered section area