6. Therefore the slant height is 10 + 15 = 2512 x
Find the slant height.
Find the radii of each circle.
Find the volume of the frustum. 10 8
1. Find x and add it to 10.
Two ~triangles =
20x = 12x+120
8x = 120
x = 15
Therefore the slant height is = 25

7. 2. Find the radii.
Draw the triangles inside both cones. 15 12 25 20
Small cone
Large cone
Since we have 3, 4, 5 triangles, the radius of the small cone is 9 and the radius of the larger cone is 15.

8. The volume of the frustum is equal to the volume of the large cone minus the volume of the smaller cone.
V = π r2h -
π r2h
V = π 152(25) π (9)2(15)
V = π π
V = 660 π

9. Find the volume of this pyramid if its base is 12, width 9, height 15
Volume of a pyramid:
V = bwh w b
Find the volume of this pyramid if its base is 12, width 9, height 15
V = 540

10. 12.6 Volume of Spheres
V = π r3