+13 A conical frustum has bases with radii of 9 and 12 and a height of 4. The total surface area of the frustum is A, in square units, and the volume of the frustum is V, in cubic units. Find A + V.
+128407 Volume = pi (h/3)(a^2 + ab + b^2) where h is the height and a, b are the radii
Surface area = pi [ (a + b) sqrt [ ( a -b)^2 + h^2 ] + a^2 + b^2 ]
Filling in what we know
pi [ (9 +12) sqrt [ (12 - 9 )^2 + 4^2 ] + 12^2 + 9^2 ] = 330pi = A
pi (4/3) (12^2 + 12*9 + 9^2 ] = 444pi = V
A + V = 330pi + 444 pi = 774 pi
